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This book chapter investigates protein kinases, pivotal enzymes governing cellular signaling, and regulation. Constituting around 2% of human genes, protein kinases play a vital role in phosphorylation, a crucial post-translational modification dictating cellular functions. Emphasizing their dynamic nature as molecular switches, the chapter explores their structural intricacies and regulatory mechanisms. It classifies protein kinases into five families based on evolutionary and structural resemblances, each contributing to diverse signaling pathways governing cell growth, metabolism, and immune responses. Dysregulation of these kinases is implicated in various diseases. The chapter discusses the significance of protein kinases in cancer therapy, highlighting targeted treatments such as small molecule inhibitors and monoclonal antibodies. It further explores their role in neurodegenerative disorders such as Alzheimer’s and Parkinson’s diseases, as well as their involvement in cardiovascular diseases, emphasizing their potential as therapeutic targets. Additionally, it sheds light on the regulatory role of protein kinases in inflammatory conditions, suggesting kinase inhibitors and monoclonal antibodies as promising strategies for managing diseases such as rheumatoid arthritis and inflammatory bowel disease. Overall, the chapter provides a comprehensive overview of protein kinases, underlining their structural diversity, regulatory mechanisms, and pivotal roles in physiological and pathological contexts, thereby highlighting their potential as promising targets for personalized medicine interventions across various diseases.
School of Biotechnology, KIIT Deemed to be University, Bhubaneswar, Odisha, India
Prajna Ritaparna
School of Biotechnology, KIIT Deemed to be University, Bhubaneswar, Odisha, India
*Address all correspondence to: ajitkudhal@gmail.com
1. Introduction
Protein kinases are a class of enzyme that is essential for cellular signaling and control. They are in charge of the phosphorylation process, which involves the transfer of phosphate groups from adenosine triphosphate (ATP) to certain target proteins, as shown in Figure 1. This post-translational alteration has the potential to significantly alter the structure, function, and location of target proteins, altering a variety of cellular processes. Protein kinases, comprising approximately 2% of all human genes, are diverse and abundant in the human genome, with around 518 kinase genes. They play a crucial role in cellular signaling, regulating a wide range of pathways. With over 280 human protein kinase structures characterized, their significance in modulating up to 30% of human proteins highlights their fundamental importance in cellular function and communication [2]. These are found in all living creatures, from bacteria to humans, and have a variety of roles in physiological processes such as cell development, proliferation, differentiation, metabolism, and apoptosis. Examples can be seen in Figure 2. They play an important role in the regulation of intracellular signaling pathways, conveying signals from external stimuli to the cell’s interior and coordinating proper physiological responses [4, 5]. Every protein kinase shares a common structural motif comprising two distinct lobes, as shown in Figure 3. To show the catalytic cycle of protein phosphorylation by a protein kinase, another simple illustration is given by using Figure 4.
Figure 1.
Protein kinases and phosphatases are pivotal enzymatic regulators within biological systems. They orchestrate the intricate dance of cellular signaling by catalyzing phosphorylation and dephosphorylation reactions. Protein kinases facilitate the amplification and propagation of incoming signals by activating specific substrates through phosphorylation. Conversely, the termination of signal transmission occurs through the dephosphorylation (inactivation) of substrates, a process meticulously orchestrated by protein phosphatases [1].
Figure 2.
Allosteric regulation mechanism of Arabidopsis serine/threonine kinase 1 (SIK1) via phosphorylation [3].
Figure 3.
Protein kinases: A unified mechanism and structural basis [6]. Source: (a) Illustration of the core catalytic cycle governing substrate phosphorylation by kinases. Commencing at the top left, ATP engages the kinase’s active site, followed by substrate binding to the same site. Subsequently, the γ-phosphate of ATP (depicted in red) is transferred to a Ser, Thr, or Tyr residue on the substrate. After phosphorylation, the substrate dissociates from the kinase. The final step portrays the release of ADP from the active site. The sequence of these steps and the rate-limiting stage can vary among different kinases. (b) Every protein kinase shares a common structural motif comprising two distinct lobes: one predominantly composed of β-sheet structures (blue) and the other featuring α-helices (green, orange, and yellow). This dual-lobed architecture forms an ATP-binding cleft, which constitutes the active site. The crystal structure of cyclin-dependent kinase-2 (CDK2) (Protein Data Bank (PDB) ID: 1QMZ) serves as a representative example. ATP is depicted as bound within the cleft (red ball-and-stick model). (c) Despite their shared structural fold, kinases target and phosphorylate diverse protein substrates, largely influenced by variations in the charge and hydrophobicity of surface residues. Electrostatic surface representations are presented for four distinct kinases: three Ser/Thr kinases—CDK2, PKA (cAMP-dependent protein kinase, PDB ID: 1ATP), and PHK (phosphorylase kinase, PDB ID: 2PHK)—as well as the tyrosine kinase domain of the insulin receptor (IRK, PDB ID: 1IRK). Positively charged surfaces are depicted in blue, while negatively charged surfaces are shown in red.
Figure 4.
The catalytic cycle of protein phosphorylation by a protein kinase: depiction of phosphate group transfer with red circles [7].
Protein kinases consist of three types of domains: a kinase domain, one or more regulatory domains (referred to as second domains), and additional domains that do not affect the kinase domain. Typically, protein kinases have a catalytic domain that binds ATP and phosphorylates the target proteins together with regulatory domains that control their activity. A conserved amino acid sequence pattern called the kinase domain is present in the catalytic domain and provides the enzymatic activity required for phosphorylation. The regulatory domains may contain areas involved in allosteric control, protein-protein interactions, or the detection of particular biological signals. Numerous protein kinases, each with a unique substrate specificity and biological function, are encoded in the human genome [8]. The preferred configuration is a polypeptide with a kinase domain and exactly one-second domain. However, other variations are also possible, such as polypeptides with different combinations of kinase domains, second domains, and additional domains [9]. The term “polypeptide” encompasses a chain of amino acids, typically the 20 naturally occurring proteinogenic alpha amino acids, and includes molecules where the kinase domain and second domain are linked by a linker, which may be peptidic or non-peptidic. Non-peptidic linkers can be polyethylene or PEG linkers, with a preferred length of less than 50, 40, 30, 20, or 10 atoms (excluding hydrogens). Alternatively, the polypeptide can use the naturally occurring linker found in the wild-type counterpart or a different peptidic linker, such as oligo glycine stretches. Polypeptides containing at least one protein kinase domain are also referred to as “Kinases,” with the preferred kinases having at least one-second domain as described above (Figures 5 and 6) [12].
Figure 5.
Structure of a prototypical protein kinase domain revealing the ATP binding site and surrounding conserved elements (INSR kinase, PDB ID: 1GAG) [10].
Figure 6.
Regulatory domains of protein kinase C: deciphering diverse membrane Signaling events [11].
Over the past two decades, our understanding of protein kinases has significantly evolved. We now recognize that protein kinases are dynamic molecules, specifically designed as highly regulated molecular switches rather than just efficient catalysts [13]. Initially, we recognized the regulatory potential of phosphorylation, but we underestimated the complexity of the protein kinase family and the vast biological networks they regulate. Sequence analysis revealed scattered conserved motifs throughout the protein kinase core, highlighting their dynamic and regulated nature. The first solved protein kinase structure, PKA, confirmed the conserved fold and revealed the active site characteristics, including the unique positioning of the ATP-binding site and the role of the Activation Loop in controlling the active site’s accessibility [14]. Because all eukaryotic protein kinases share a conserved catalytic core, the crystal structure of cAMP-dependent protein kinase (PKA) allowed us for the first time to begin understanding the molecular basis for the functioning of one protein kinase. This discovery shed light on the entire family of eukaryotic protein kinases [15]. Eukaryote protein kinases (EPKs) are dynamic and flexible molecules that have evolved as molecular switches, transitioning between “on” and “off” states. The integration of sequence, structure, and dynamics is crucial to understand their function and regulation. The landmark crystal structure of the first protein kinase, PKA, provided insights into the conserved structural core of kinases, featuring N- and C-lobes connected by a hinge. The ATP-binding site is located at the interface between these lobes, with surfaces formed by β-sheets. The lobes are connected by the hinge, and the interface encompasses key structural elements like the C-helix, activation loop (A-loop), and substrate recognition sites. Understanding the different structural and functional states of protein kinases aids in the development of kinase inhibitors [16]. Protein kinases function as molecular switches that can be toggled between an “off” state and an “on” state in response to signals. One regulatory mechanism involves pseudo substrate inhibition, where a sequence from the kinase itself or another protein occupies the protein substrate-binding site, preventing substrate binding and inhibiting kinase activity. Inactive kinases may also have key active site residues displaced from their proper positions. In the active state, kinases exhibit a specific conformation characterized by the alignment of catalytic and regulatory residues, forming a regulatory R-spine and a catalytic C-spine. The active conformation also stabilizes the A-loop, which acts as a platform for protein substrate binding. In contrast, inactive kinase structures display a range of conformations, often involving disruption of interactions between the C-helix and the A-loop. The C-helix, a critical structural element, contributes to the allosteric behavior of kinases and is involved in interactions that define kinase activity. Kinases can transition between an active conformation (C-helix in) and an inactive conformation (C-helix out). Autoinhibitory features, such as refolded conformations of the A-loop or specific interactions involving the C-helix, contribute to stabilizing the inactive states. The αC-β4 loop, a highly ordered structure, serves to connect the C-helix and β4 and plays a role in regulating kinase activity and forming dimer interfaces. The confirmation of the A-loop is also influenced by a tripeptide motif known as the DFG motif, which acts as a pivot point. Kinases can adopt different DFG conformations, including DFG-in, DFG-out, and intermediate conformations. The conformational diversity of kinases, including the positions of the C-helix and the DFG motif, affects the geometry of the ATP-binding site and provides opportunities for designing kinase inhibitors that target specific pockets within the kinase structure. Understanding these regulatory mechanisms and conformational changes is crucial for developing effective kinase inhibitors and advancing our knowledge of kinase biology (Figures 5–7) [18].
Figure 7.
Structure and subdomains of a prototypical protein kinase domain [17]. Source: (A) The architecture of a representative protein kinase domain is depicted, with the protein backbone visualized in a gray cartoon representation, and the peptide substrate displayed in orange. The non-hydrolyzable ATP analog, AMP-PNP, is illustrated in yellow. This structural representation is derived from the PDB structure 1ir3. (B) Schematic delineation of the ATP binding site, partitioned into distinct subdomains.
Based on their evolutionary connections and structural resemblances, Protein Kinases are divided into five families. Those are serine/threonine kinases, tyrosine kinases, aspartic acid/glutamic acid-specific, dual-specificity kinases and histidine-specific kinases. These are a few well-known kinase families. Each family controls different signaling pathways and target proteins. Sometimes kinases work in a series of cellular signals forming a phosphorylation cascade [19]. Cancer, neurological illnesses, and autoimmune diseases have all been linked to the dysregulation of protein kinase activity. As a result, many kinase inhibitors have been created and used in targeted therapy. Protein kinases have thus become desirable targets for therapeutic research. Serine/threonine protein kinases (ST-PKs) perform critical roles in controlling physiological processes such as cell cycle progression, signal transduction, and protein synthesis. They phosphorylate serine and threonine residues in target proteins. Tyrosine protein kinases (TKs), which are engaged in important signaling pathways affecting cell growth, differentiation, and metabolism, have as their sole target tyrosine residues. For bacteria to recognize and react to environmental changes, signal transduction, which is made possible by histidine-specific kinases, is crucial. Having the capacity to phosphorylate both serine/threonine and tyrosine residues, dual-specificity protein kinases are involved in a variety of biological functions, such as cell cycle regulation and stress responses. Finally, aspartic acid/glutamic acid-specific protein kinases phosphorylate aspartic acid and glutamic acid residues; however, they are less well-studied than the other groups in terms of their roles and regulation mechanisms. Collectively, these many protein kinases help to regulate physiological activities in a complex way and give phosphorylation events within signaling networks a certain level of specificity. Kinases fall under EC number 2.7, which is assigned by the enzyme commission [20].
4.1 Serine/threonine protein kinases
Serine/threonine protein kinases (STKs) are a diverse group of enzymes that phosphorylate the hydroxyl (OH) group of serine or threonine residues in target proteins. They play a crucial role in regulating various cellular processes and are involved in important post-translational modifications. There are several types of STKs, including CK2 (casein kinase 2), which is known for its involvement in diverse cellular functions. Protein kinase A (PKA) consists of two domains and is responsible for phosphorylating specific substrates. Protein kinase C (PKC) is a family of kinases divided into three subfamilies based on their second messenger requirements. Mos/Raf kinases are part of the MAPKK kinase family and are involved in cell growth stimulation. Mitogen-activated protein kinases (MAPKs) respond to extracellular stimuli and regulate various cellular activities. Ca2+/calmodulin-dependent protein kinases (CAMKs) are primarily regulated by the Ca2+/calmodulin complex. Protein kinase B (AKT) is an important kinase involved in cell proliferation and insulin actions. Cyclin-dependent kinases (CDKs) play a central role in cell cycle regulation, while protein kinase D (PKD) is activated by protein kinase C and regulates various cellular functions such as cell growth, migration, and apoptosis. PKD is also implicated in cardiovascular, neuronal, immune, and tumor-related processes, highlighting its multifaceted roles in different biological contexts. Overall, the diverse types of serine/threonine protein kinases contribute to the intricate regulation of cellular processes and serve as crucial signaling components in various physiological and pathological conditions [2, 20].
4.2 Tyrosine kinases
Tyrosine kinases play a pivotal role in cellular functions by phosphorylating tyrosine residues and acting as molecular switches. They comprise a diverse group of enzymes involved in various signaling cascades, with NRTKs, RTKs, and nuclear tyrosine protein kinases collectively contributing to the intricate landscape of tyrosine kinase-mediated signaling pathways. Tyrosine kinases encompass three major categories: non-receptor tyrosine protein kinases (NRTKs), receptor tyrosine kinases (RTKs), and nuclear tyrosine protein kinases. NRTKs possess crucial domains such as SH1, SH2, SH3, PH, and PTB, which regulate catalytic reactions, enzyme localization, activity, and molecular interactions. With over 30 members across 11 families, NRTKs mediate signal transduction from growth factor receptors, cytokine receptors, lymphocyte antigen receptors, and integrins. Examples include the SRC kinase family, JAK kinase family, and Sky/ZAP-70 family, each involved in distinct signaling pathways and cellular functions. On the other hand, RTKs are transmembrane proteins that transmit signals upon ligand binding, regulating cell growth, differentiation, and development. Nuclear tyrosine protein kinases participate in transcriptional processes and cell cycle regulation [20, 21].
4.3 Histidine protein kinases
Histidine protein kinases phosphorylate histidine residues in substrate proteins. They can be categorized into two main types: two-component histidine protein kinases and two-component mammalian histidine protein kinases. Two-component histidine protein kinases are involved in regulating responses to environmental stimuli. In prokaryotes, histidine kinases are sensor proteins that initiate signaling pathways known as two-component systems (TCSs) in response to various environmental cues. TCSs typically consist of a histidine kinase and a corresponding response regulator that often acts as a transcription factor. The enzymatic activity of a histidine kinase involves the transfer of a phosphate group from ATP to a protein, resulting in the conversion of ATP to ADP and the phosphorylation of histidine. Most histidine kinases are homodimers and possess auto-kinase, phosphotransferase, and phosphatase activities. Histidine kinases are widely present in various organisms such as bacteria, archaea, slime molds, fungi, and plants. They play a crucial role in two-component signal transduction pathways. Examples of these pathways include the bacterial phosphoenolpyruvate: the sugar phosphotransferase system (PTS) and the histidine kinases involved in different signal transduction processes [20, 22].
4.4 Dual-specificity protein kinases
Dual-specific protein kinases exhibit kinase activity toward both serine/threonine and tyrosine residues. They are capable of acting as both serine/threonine kinases and tyrosine kinases. MEKs, which are involved in MAP pathways, serve as prominent examples of dual-specificity kinases. Additionally, there are several other well-known dual-specificity kinases, such as ADK1, CLK1, CLK2, CLK3, CLK4, DSTYK, DYRK1A, DYRK1B, DYRK2, DYRK3, DYRK4, Mps1p, TESK1, TESK2, and TTK. An instance of a dual-specificity protein kinase is MEK5, which phosphorylates the TEY activation motif to activate ERK5 [20, 23, 24].
4.5 Aspartic acid/glutamic acid-specific protein kinases
Protein kinases that are specific to aspartic acid/glutamic acid can phosphorylate aspartate/glutamate. The phosphorus receptor is a part of the protein’s acyl group [20], for example, MEK1 protein kinase. Through the activation of several regulatory kinases, the dual-specificity kinase MEK1 regulates Golgi disassembly. MEK1 is an essential component of the tripeptide signaling module that makes up the MAP kinase signal transduction pathway [24].
Protein kinases, which play pivotal roles in regulating numerous cellular processes, are commonly linked to various diseases, serving as either causal factors or potential targets for therapeutic intervention. Here are some diseases along with the protein kinases associated with them. Some examples are shown in Figure 8.
Figure 8.
Protein kinases: an examination of their overview, classification, and therapeutic prospects [25].
5.1 Targeting protein kinases in cancer therapeutics
Dysregulated protein kinase activity is a hallmark of many cancers. Oncogenic protein kinases drive tumor growth, angiogenesis, and metastasis. Targeting these kinases has shown significant promise in cancer therapeutics. Small molecule inhibitors, such as Imatinib targeting BCR-ABL [26] in chronic myeloid leukemia, have revolutionized cancer treatment. Monoclonal antibodies, such as Trastuzumab targeting HER2 in breast cancer [27], have been successful in blocking kinase activity and inhibiting tumor growth. Gene therapy approaches, such as using viral vectors to deliver RNA interference against oncogenic kinases, hold potential in personalized cancer treatments. An example is explained in Figure 9.
Figure 9.
Serine/threonine phosphorylation in cytokine-mediated signal transduction pathways | Leukemia research [28].
5.2 Protein kinases in neurodegenerative disorders
Protein kinases are implicated in the pathogenesis of neurodegenerative disorders, including Alzheimer’s and Parkinson’s diseases. Abnormal phosphorylation of tau protein by kinases like glycogen synthase kinase-3β (GSK-3β) contributes to neurofibrillary tangle formation in Alzheimer’s disease. Inhibitors targeting GSK-3β [29] have shown promise in preclinical studies. Similarly, aberrant protein kinase activity, including that of leucine-rich repeat kinase 2 (LRRK2), is implicated in Parkinson’s disease. Inhibitors targeting LRRK2 have been developed and are being evaluated in clinical trials. Additional neurological disorders are elucidated in Figures 10–12.
Figure 10.
Impact of protein kinases (PKA, PKB, and PKC) on postischemic brain injury progression and associated cell Signaling events [30]. This figure delineates the pivotal roles played by three crucial protein kinases—protein kinase A (PKA), protein kinase B (PKB), and protein kinase C (PKC)—in the progression of postischemic brain injury, as well as their associated cell signaling cascades. The key molecular components involved in these pathways are identified: BAD (Bcl-2-associated death promoter), cAMP (cyclic adenosine monophosphate), DAG (diacylglycerol), GSK-3 (glycogen synthase kinase three), IKK alpha (I kappa B kinase subunit alpha), IP3 (inositol triphosphate), mTOR (mechanistic target of rapamycin), PIP2 (phosphatidylinositol biphosphate), PKA (protein kinase A), PKC (protein kinase C), PLC (phospholipase C), RACK (receptor for activated C-kinase), and S6K1 (protein S6 kinase one).
Figure 11.
Regulation of brain-type creatine kinase (CKB) in Huntington’s disease (HD) [31]. This figure caption provides a concise overview of potential mechanisms underlying the regulation of the creatine kinase (CK)/phosphocreatine (PCr) system by mutant huntingtin (Htt) in Huntington’s disease (HD). It highlights the downregulation of both CKB expression and transcript levels in HD. Solid lines indicate pathways supported by experimental evidence, while dotted lines represent hypothesized pathways. It is known that mutant Htt interacts with and activates p53, which, in turn, suppresses the CKB promoter.
Figure 12.
Targets of CK2 in neurodegenerative disorders. This figure highlights the involvement of CK2 in various neurodegenerative diseases, indicating its impact on disease-related processes using color-coded shapes. Red shapes represent CK2 targets that contribute to pathological functions, blue shapes represent proteins through which CK2 may exert protective effects against the disease, and gray shapes denote CK2-dependent phosphorylation events that do not have a direct disease-related effect [32]. Source: (a) Parkinson’s Disease (PD): CK2 promotes α-synuclein aggregation in Lewis bodies (LB) by phosphorylating Ser129, although this site is also targeted by other protein kinases. (b) Alzheimer’s Disease (AD): CK2 plays a role in the 5-HT4 receptor-stimulated induction of α-secretase activity, reducing Aβ production through the non-amyloidogenic pathway. However, CK2 induces tau hyperphosphorylation by phosphorylating SET, an inhibitor of the PP2A phosphatase, leading to its cytosolic localization and binding to PP2A. CK2 also phosphorylates KLC1, causing FAT impairment. CK2 targets PS-2, but this phosphorylation does not affect APP processing. (c) Huntington’s Disease (HD): CK2 increases phosphorylation at Ser13 and Ser16 of HTT, which are hypo-phosphorylated in the polyQ-HTT mutant, thereby reducing cellular toxicity. (d) Spinocerebellar Ataxia Type 3 (SCA3): CK2 associates with and phosphorylates ataxin-3, promoting its nuclear localization and stabilization, and enhancing inclusion formation. (e) Amyotrophic Lateral Sclerosis (ALS): CK2 is a potential kinase of TDP43, a major component of protein aggregates in motor neurons. Phosphorylation by CK2 decreases TDP43’s propensity to aggregate. CK2 also phosphorylates cyclin F, negatively regulating the E3 ligase activity of the SKP1/cullin1/F-box (SCF)-E3 ligase complex and reducing aberrant protein ubiquitination typically observed in ALS.
5.3 Protein kinases and cardiovascular diseases
Protein kinases play a critical role in cardiovascular functions and are involved in the pathogenesis of cardiovascular diseases. For instance, protein kinase C (PKC) isoforms are known to regulate cardiac contractility, hypertrophy, and fibrosis. PKC inhibitors, such as Enzastaurin, have shown the potential to reduce myocardial damage in heart failure. In addition, the mitogen-activated protein kinase (MAPK) pathway is involved in vascular smooth muscle cell proliferation and migration. Inhibitors targeting MAPK kinases have shown promise in preventing restenosis after angioplasty [33].
5.4 Protein kinases in inflammatory conditions
Inflammation is tightly regulated by protein kinases, which modulate the activity of key transcription factors and inflammatory mediators. Dysregulated kinase signaling can lead to chronic inflammation and contribute to the pathogenesis of inflammatory diseases. Small molecule inhibitors targeting kinases, such as Janus kinases (JAKs) and spleen tyrosine kinase (SYK), have shown efficacy in inflammatory conditions like rheumatoid arthritis and inflammatory bowel disease. Monoclonal antibodies targeting cytokine receptors and downstream kinases have also emerged as effective therapeutics in various inflammatory diseases [34]. A comprehensive list of protein kinases with their descriptions and associated diseases is depicted in Table 1.
Catalytic reaction of the kinase, enzyme localization, signal transduction of various growth factor receptors, cytokine receptors, lymphocyte antigen receptors, and adhesion molecule integrins.
In conclusion, protein kinases are pivotal players in cellular signaling and control, regulating a wide array of physiological processes through post-translational phosphorylation. The diversity and abundance of protein kinases in the human genome underscore their fundamental importance in cellular function and communication. Protein kinases are dynamic molecules, serving as highly regulated molecular switches rather than mere catalysts. Their structural and functional diversity allows for precise control of cellular responses, making them attractive targets for therapeutic research.
The classification of protein kinases into distinct families, including serine/threonine kinases, tyrosine kinases, histidine-specific kinases, dual-specificity kinases, and aspartic acid/glutamic acid-specific kinases, highlights the intricate nature of phosphorylation events within signaling networks. These kinases play critical roles in a wide range of physiological and pathological conditions, including cancer, neurodegenerative disorders, cardiovascular diseases, and inflammatory conditions.
The development of kinase inhibitors, monoclonal antibodies, and gene therapy approaches has shown significant promise in cancer therapeutics, offering personalized treatment options. In neurodegenerative disorders, targeting specific kinases involved in abnormal phosphorylation pathways holds potential for disease-modifying interventions. Protein kinases also play a crucial role in cardiovascular functions, and kinase inhibitors have the potential to mitigate myocardial damage and prevent restenosis after angioplasty. Furthermore, in inflammatory conditions, kinase inhibitors and monoclonal antibodies have emerged as effective therapeutics, providing new avenues for managing chronic inflammation.
Overall, the complex and versatile nature of protein kinases positions them as central regulators of cellular processes and attractive targets for therapeutic interventions across a spectrum of diseases. Continued research into the structure, function, and regulation of protein kinases is essential for the development of innovative treatments and a deeper understanding of cellular biology.
The authors declare that they have no conflict of interest.
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Written By
Ajit Kumar Dhal and Prajna Ritaparna
Submitted: 07 July 2023Reviewed: 25 September 2023Published: 05 July 2024
Open access peer-reviewed chapter - ONLINE FIRST
