Dimerization/Docking domain of Cyclic GMP-dependent Protein Kinase I; Cyclic GMP-dependent Protein Kinase I (PKG1 or cGKI) is a Serine/Threonine Kinase (STK), catalyzing the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. cGKI exists as two splice variants, cGKI-alpha and cGKI-beta. They contain an N-terminal regulatory domain containing a dimerization/docking region and an autoinhibitory pseudosubstrate region, two cGMP-binding domains, and a C-terminal catalytic domain. Binding of cGMP to both binding sites releases the inhibition of the catalytic center by the pseudosubstrate region, allowing autophosphorylation and activation of the kinase. cGKI is a soluble protein expressed in all smooth muscles, platelets, cerebellum, and kidney. It is also expressed at lower concentrations in other tissues. It is involved in the regulation of smooth muscle tone, smooth cell proliferation, and platelet activation. The dimerization/docking (D/D) domain is a leucine/isoleucine zipper that mediates both homodimerization and interaction with isotype-specific G-kinase-anchoring proteins (GKAPs). The D/D domain of the two variants (alpha and beta) differ, allowing their targeting to different subcellular compartments and intracellular substrates.

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gi 119583070 192 KKTEEVVLKDGRIERLKLELERKDAEIQKLKN 223
Cdd:cd12083    6 EKTEELRKKDERIRELEQELQEKDEEIQELRS 37

Dimerization/Docking domain of Cyclic GMP-dependent Protein Kinase I; Cyclic GMP-dependent Protein Kinase I (PKG1 or cGKI) is a Serine/Threonine Kinase (STK), catalyzing the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. cGKI exists as two splice variants, cGKI-alpha and cGKI-beta. They contain an N-terminal regulatory domain containing a dimerization/docking region and an autoinhibitory pseudosubstrate region, two cGMP-binding domains, and a C-terminal catalytic domain. Binding of cGMP to both binding sites releases the inhibition of the catalytic center by the pseudosubstrate region, allowing autophosphorylation and activation of the kinase. cGKI is a soluble protein expressed in all smooth muscles, platelets, cerebellum, and kidney. It is also expressed at lower concentrations in other tissues. It is involved in the regulation of smooth muscle tone, smooth cell proliferation, and platelet activation. The dimerization/docking (D/D) domain is a leucine/isoleucine zipper that mediates both homodimerization and interaction with isotype-specific G-kinase-anchoring proteins (GKAPs). The D/D domain of the two variants (alpha and beta) differ, allowing their targeting to different subcellular compartments and intracellular substrates.

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                 ....*....|....*....|....*....|..
gi 119583070 192 KKTEEVVLKDGRIERLKLELERKDAEIQKLKN 223
Cdd:cd12083    6 EKTEELRKKDERIRELEQELQEKDEEIQELRS 37

Mediator complex subunit 28; Mediator is a large complex of up to 33 proteins that is conserved from plants to fungi to humans - the number and representation of individual subunits varying with species. It is arranged into four different sections, a core, a head, a tail and a kinase-activity part, and the number of subunits within each of these is what varies with species. Overall, Mediator regulates the transcriptional activity of RNA polymerase II but it would appear that each of the four different sections has a slightly different function. Subunit Med28 of the Mediator may function as a scaffolding protein within Mediator by maintaining the stability of a submodule within the head module, and components of this submodule act together in a gene-regulatory programme to suppress smooth muscle cell differentiation. Thus, mammalian Mediator subunit Med28 functions as a repressor of smooth muscle-cell differentiation, which could have implications for disorders associated with abnormalities in smooth muscle cell growth and differentiation, including atherosclerosis, asthma, hypertension, and smooth muscle tumours.

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gi 119583070  192 KKTEEVVLKDgrIERLKLELERKDAEIQKLKNVITQWE 229
Cdd:pfam11594  63 QKPEEVLKEE--IAELRAELERKDELIKKHKEKIQEWQ 98