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Mitogen-activated protein kinase 1 (MAPK1) is also known as "extracellular signal-regulated kinase 2" (ERK2). Two similar (85% sequence identity) protein kinases were originally called ERK1 and ERK2. They were found during a search for protein kinases that are rapidly phosphorylated after activation of cell surface tyrosine kinasessuch as the epidermal growth factor receptor. Phosphorylation of ERKs leads to the activation of their kinase activity. The molecular events linking cell surface receptors to activation of ERKs are complex. It was found that RasGTP-binding proteins are involved in the activation of ERKs. Another protein kinase, Raf-1, was shown to phosphorylate a "MAPK kinase", thus qualifying as a "MAPK kinase kinase". The MAPK kinase was named "MAPK/ERK kinase" (MEK). Receptor-linked tyrosine kinases, Ras, Raf, MEK and MAPK could be fitted into a signaling cascade linking an extracellular signal to MAPK activation. Transgenic gene knockoutmice lacking MAPK1 have major defects in early development.

Non muscle Myosins are required for cytokinesis at the end of cell division, when a contractile ring near the plasmalemma divides the cytoplasm of the daughter cells. They are involved in cytoplasmic streaming movements in tissues, and especially in activation of motile cells such as fibroblasts and macrophages. Activation of non-muscle myosin-II is achieved by phosphorylation of Ser33 in the motif KKRPQRATSN by a dedicated, Ca +2 Calmodulin regulated light chain kinase (MLCK).

Tachykinin-1 (TAC1) belongs to the tachykinin peptide hormone family. TAC1 are a family of peptides which have similar biologic activities and share a common C-terminal sequence, phe-X-gly-leu-met-NH2, however they have distinct N-terminal sequences that convey receptor specificities. TAC1 is assumed to act as neurotransmitters which interact with nerve receptors and smooth muscle cells. TAC1 induces behavioral responses and serves as vasodilators and secretagogues.

Tachykinin-3 belongs to the substance P-related tachykinin family. Tachykinins are active peptides that stimulate neurons, induce behavioral responses, are effective vasodilators and secretagogues, and contract (directly or indirectly) many smooth muscles. TAC3 and its receptor are essential switches of regulator of human puberty, regulated by the brain through the release of the GnRH which starts a chain of processes which eventually lead to the production of sex hormones.
During pregnancy, the expression of TAC3 is restricted to the outer syncytiotrophoblast of the placenta, significant concentrations of TAC3 can be identified in plasma as early as week 9, and plasma concentrations of TAC3 are grossly elevated in pregnancy-induced hypertension and pre-eclampsia. Higher Tachykinin-3 concentrations in normotensive pregnant women may be caused by the advanced gestational age and/or the result of a negative interaction of other vasoactive substances. TAC3 has a role in the continuance of high placental blood flow in normal pregnancy.

TIPIN is a member of the CSM3 family. TIPIN protein is essential for normal advancement of S-phase and vital for cell existence after DNA damage or replication stress. TIPIN is specifically necessary for the ATR - CHEK1 pathway in the replication checkpoint induced by ultraviolet light.

Myosin light polypeptide 6 (MYL6) is a hexameric ATPase cellular motor protein. MYL6 is composed of 2 heavy chains, 2 nonphosphorylatable alkali light chains, and 2o phosphorylatable regulatory light chains. MYL6 is a myosin alkali light chain which is expressed in smooth muscle and non-muscle tissues. MYL6 partakes in generating the force for cellular movements, thus having an imperative role in overall cellular function.

MYL9 is one of the numerous regulatory myosin light chains. Myosin which is a structural component of the muscle consists of 2 heavy chains and 4 light chains. MYL9 is a myosin light chain regulates muscle contraction by modulating the ATPase activity of myosin heads. MYL9 binds calcium and is activated by myosin light chain kinase. Regulatory myosin light chains regulate contraction in smooth muscle and non-muscle cells via phosphorylation by MLCK (myosin light chain kinase). Phosphorylation of regulatory myosin light chains is catalyzed by MLCK in the presence of calcium and calmodulin and it increases the actin-activated myosin ATPase activity, thus regulates the contractile activity.

The protein encoded by LAMP2 belongs to a family of membrane glycoproteins. This glycoprotein provides selectins with carbohydrate ligands LAMP2 takes part in tumor cell metastasis and in addition has a role in the protection, maintenance, and adhesion of the lysosome. The effect of alternative splicing of this gene is multiple transcript variants encoding distinct proteins.

Macrophage Inflammatory Proteins (MIP) belong to the family of chemotactic cytokines known as chemokines. In humans, there are two major forms, MIP-1a and MIP-1b that are now officially named CCL3 and CCL4 respectively. Both are major factors produced by macrophages after they are stimulated with bacterial endotoxins. They activate human granulocytes (neutrophils, eosinophils and basophils) which can lead to acute neutrophilic inflammation. They also induce the synthesis and release of other pro-inflammatory cytokines such as interleukin 1 (IL-1), IL-6 and TNF-a from fibroblasts and macrophages. The genes for CCL3 and CCL4 are both located on human chromosome 17.

GCSAM is a protein which functions in signal transduction pathways and whose expression raises in germinal cell lymphomas. GCSAM contains a putative PDZ-interacting domain, an immunoreceptor tyrosine-based activation motif (ITAM), and two putative SH2 binding sites. In B cells, GCSAM expression is particularly induced by interleukin-4.

TFB1M is a member of the methyltransferase superfamily. TFB1M is a dimethyltransferase which methylates mitochondrial 12S rRNA at the conserved stem loop. The TFB1M protein also is part of the basal mitochondrial transcription complex and is required for mitochondrial gene expression. TFB1M stimulates transcription independently of the methyltransferase activity.

Myosin is a hexameric ATPase cellular motor protein, which is composed of 2 heavy chains, 2 non-phosphorylatable alkali light chains, and 2 phosphorylatable regulatory light chains.
MYL1 gene encodes a myosin alkali light chain expressed in fast skeletal muscle. Two transcript variants have been identified for the MYL1 gene. In humans MYL1 is localized to chromosome 2q32.1-qter. The Myl1 locus encodes two alkali myosin light chains- Mlc1f and Mlc3f, from two promoters that are differentially regulated throughout development. The Mlc1f promoter is active in embryonic, fetal and adult fast skeletal muscle while the Mlc3f promoter is upregulated during fetal development and stays on in adult fast skeletal muscle.

Translocase of Outer Mitochondrial Membrane 34 (TOMM34) which is found in the cytoplasm and sometimes associated with the outer mitochondrial membrane is involved in the import of precursor proteins into mitochondria. TOMM34 has a chaperone-like activity, binding the mature portion of unfolded proteins and aiding their import into mitochondria. TOMM34 has a weak ATPase activity and contains 6 TPR repeats.

MAF1 resembles Maf1 which is a Saccharomyces cerevisiae – a highly conserved protein in eukaryotic cells, localized to the nucleus. MAF1 Interacts with BRF2, MAF1 and functions as a mediator for signals which explicitly inhibit RNA polymerase III (Pol III) activity by inhibiting the association of TFIIIB to DNA. MAF1 reacts to modifications in the cellular environment and represses pol III transcription.

KPNB1 is a member of the importin beta family. The KPNB1 protein is engaged in nuclear protein import, either by coupling itself with an adapter protein (e.g., importin-alpha subunit which binds to nuclear localization signals (NLS) in cargo substrates), or by functioning autonomously as a nuclear transport receptor (acts as NLS receptor, docking of the importin/substrate complex to the nuclear pore complex).

SPA17 is a protein present at the cell surface. SPA17 was characterized by its participation in the binding of sperm to the zona pellucida of the oocyte. The central portion of SPA17 has carbohydrate binding motifs and likely takes part in cell-cell adhesion functions such as immune cell migration and metastasis.

Progesterone-Associated Endometrial Protein (PAEP) is a member of the kernel lipocalin super family whose members share rather low sequence similarity but have highly conserved exon/intron structure and three-dimensional protein folding. Most lipocalins are clustered on the long arm of chromosome 9. PAEP protein has been previously referred to as pregnancy-associated endometrial alpha-2-globulin, placental protein 14, and glycodelin.

Energy Homeostasis Associated (ENHO) participates in glucose homeostasis maintenance and lipid metabolism. ENHO is expressed in the liver and the brain. The role of ENHO in obesity or diabetes is studied.

CCL28 is part of the subfamily of small cytokine CC genes. CCL28 shows chemotactic activity for resting CD4 or CD8 T cells and eosinophils. CCL28 binds to chemokine receptors CCR3 and CCR10. CCL28 is involved in the physiology of extracutaneous epithelial tissues, including diverse mucosal organs. CCL28 mediates mucosal immunity in HIV exposure and infection. CCL28 is involved in the pathogenesis of inflammatory skin diseases.
Human CCL28 cDNA encodes a 127 amino acid residue precursor protein with a putative 22 amino acid residue signal peptide that is cleaved to produce the 105 amino acid residue mature protein. Human and mouse CCL28 are highly conserved, sharing 83% amino acid identity in their mature regions. CCL28 shares the most homology with CCL27/CTACK. Human and mouse CCL28 RNA expression was found to be highest in normal and pathologic colon with the protein being expressed by epithelial cells. Human CCL28 RNA was also present in normal and asthmatic lung tissues.

Synaptobrevin 2 which is an 18 kDa integral membrane protein localized to the cytoplasmic surface of synaptic vesicle, consists of a proline-rich N-terminal region, a highly conserved hydrophilic domain, followed by a transmembrane anchor and a C-terminal. Synaptobrevin 2 is predominantly expressed in Langerhans islets and glomerular cells. The N-terminal domain of the protein (residues 1-89) forms a specific SNARE complex with the target membrane-associated t- or Q-SNAREs syntaxin 1 and SNAP-25.

Lamin-A is a major component of the nuclear lamina, a dynamic meshwork located just under the nuclear envelope and it is encoded by lamin A/C gene (LMNA).
Lamin-A is synthesized as Prelamin A, a longer precursor that in vivo goes through a serial post-translational modifications that lead to mature Lamin A.
Diverse mutations in the Lamin A/C gene are associated with different diseases that are collectively called laminophaties, including Emery-Dreifuss muscular dystrophy, familiar partial lipodystrophy, limb girdle muscular dystrophy, dilated cardiomyopathy, Charcot-Marie-Tooth disease, and Hutchinson-Gilford progeria syndrome.

CTNNBIP1 binds CTNNB1 and avoids interaction between CTNNB1 and TCF (T-cell transcription factor) family members. CTNNBIP1 is a negative regulator of the Wnt signaling pathway.

SNAP23 is a non-neuronal SNAP25 protein homologue and a target SNARE ubiquitously expressed on the plasma membrane and other intracellular membranes. SNAP23 is involved in exocytotic membrane fusion in most cells that do not express SNAP-25. SNAP23 is an essential component of the high affinity receptor for the general membrane fusion machinery and an crucial regulator of transport vesicle docking and fusion. SNAP23 is phosphorylated in platelets through cell activation during a protein kinase C-related mechanism at two or more sites. SNAP23, the ubiqitously expressed homologue of SNAP25, interacts directly with ubiquitous kinesin heavy chain (uKHC). SNAP-23 is expressed in human eosinophils and is a candidates for association with VAMP-2 during docking, which is followed by exocytosis.