Gene Protein kinase

The abundance of many protein kinases in cells is an indication of the great importance of protein phosphorylation in cellular regulation. Exactly 113 protein kinase genes have been recognized in yeast, and it is estimated that the human genome encodes more than 1000 different protein kinases. Tyrosine kinases (protein kinases that phosphorylate Tyr residues) occur only in multicellular organisms (yeast has no tyrosine kinases). Tyrosine kinases are components of signaling pathways involved in cell-cell communication (see Chapter 34). 

AMP-activated protein kinases are heterotrimeric complexes comprised of catalytic a subunits and regulatory (3 and y subunits (Table 1). Each subunit is encoded by at least two genes, some of which can also be subject to alternate splicing, leading to a diverse array of possible heterotrimeric combinations. 

CREB stands for cyclic-AMP response element (CRE) binding protein and is a transcription factor. When phosphorylated by cyclic AMP- and cyclic GMP-dependent Protein Kinases or other protein kinases it binds to gene promoters that contain a specific binding site. After binding, the respective transcription activity is modulated. 

Mitogen activated protein kinase (MARK) cascades are three kinase modules activated by phosphorylation. The three kinase modules are composed of a MAPK, a MAPKK, and a MAPKKK. There are multiple members of each component of the MAPK cascade that are conserved from yeast to human. Activation of selective MAPK modules by specific stimuli regulates cell functions such as gene expression, adhesion, migration, differ entiation, and apoptosis. 

Activation of Mi, M3, and M5 mAChRs does not only lead to the generation of IP3 followed by the mobilization of intracellular Ca2+, but also results in the stimulation of phospholipase A2, phospholipase D, and various tyrosine kinases. Similarly, M2 and M4 receptor activation does not only mediate the inhibition of adenylyl cyclase, but also induces other biochemical responses including augmentation of phospholipase A2 activity. Moreover, the stimulation of different mAChR subtypes is also linked to the activation of different classes of mitogen-activated protein kinases (MAP kinases), resulting in specific effects on gene expression and cell growth or differentiation. 

Ras activates a number of pathways among them is the mitogen-activated protein (MAP) kinases, which transmit signals downstream to other protein kinases and gene regulatory proteins... 

Hofmann F, Feil R, Kleppisch T et al (2006) Function of cGMP-dependent protein kinases as revealed by gene deletion. Physiol Rev 86 1-23. 

Genes involved in the uptake and degradation of tocopherols - Genes implicated with lipid uptake and. Mi / °f J - Protein kinase C (PKC) - Cyclooxygenase - 5-Lipoxygenase - Cytokine release (IL-1P)... 

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