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FK506 Binding Protein 5 (FKBP5) belongs to the immunophilin protein family, which has a role in immunoregulation and basic cellular processes involving protein folding and trafficking. FKBP5 is a cis-trans prolyl isomerase, which binds to the immunosuppressants FK506 and rapamycin. FKBP5 is an immunophilin protein with PPIase and co-chaperone activities. FKBP5 is assumed to mediate calcineurin inhibition. FKBP5 is a component of unligated steroid receptors heterocomplexes through interaction with heat-shock protein 90 (HSP90). In addition, FKBP5 interacts functionally with mature hetero-oligomeric progesterone receptor complexes along with the 90 kDa heat shock protein and P23 protein.

Leukocyte-associated immunoglobulin-like receptor 2 (LAIR2) is a secreted, 131 amino acids protein which contains one IglikeC2 type domain, rendering it a member of the Ig superfamily. Even though one is secreted and one is membrane bound, the 2 LAIR proteins are assumed to have evolved from a common gene ancestor and seem to share similar adhesion profiles, suggesting that LAIR2 may compete with LAIR1 for ligand binding. LAIR2 was discovered by its similarity to LAIR1, which is an inhibitory receptor present on mononuclear leukocytes. The LAIR2 gene maps to a region of 19q13.4, dubbed the leukocyte receptor cluster, which contains 29 genes in the immunoglobulin superfamily, including LAIR1. The function of the LAIR2 protein is unknown, though it is assumed to be secreted and may help modulate mucosal tolerance.

Endothelial cells express three different vascular endothelial growth factor (VEGF) receptors, belonging to the family of receptor tyrosine kinases (RTKs). They are named VEGFR-1 (Flt-1), VEGFR-2 (KDR/Flk-1), VEGFR-3 (Flt-4). Their expression is almost exclusively restricted to endothelial cells, but VEGFR-1 can also be found on monocytes. All VEGF-receptors have seven immunoglobulin-like extracellular domains, a single transmembrane region and an intracellular split tyrosine kinase domain. VEGFR-2 has a lower affinity for VEGF than the Flt-1 receptor, but a higher signaling activity. Mitogenic activity in endothelial cells is mainly mediated by VEGFR-2 leading to their proliferation.
Differential splicing of the flt-1 gene leads to the formation of a secreted, soluble variant of VEGFR-1 (sVEGFR-1). No naturally occuring, secreted forms of VEGFR-2 have so far been reported. The binding of VEGF165 to VEGFR-2 is dependent on heparin.

JAM3 belongs to the junctional adhesion molecule protein family and functions as a receptor for another member of this family. JAM3 plays a part in cell-cell adhesion. The soluble form of JAM3 is a mediator of angiogenesis. JAM3 is a counter-receptor for ITGAM, mediating leukocyte-platelet interactions and is involved in the regulation of transepithelial migration of polymorphonuclear neutrophils (PMN). A mutation in an intron of the JAM3 gene is linked with hemorrhagic destruction of the brain, subependymal calcification, and congenital cataracts.

S100A1 is a member of the S100 family of calcium binding proteins with EF-hand type Ca+2 binding motive. S100A1 (Calcium Binding Protein A1) is involved in the activation of sarcoplasmatic calcium release and the regulation of intermediate filament polymerization. S100A1 may function in stimulation of Ca2+-induced Ca2+ release, inhibition of microtubule assembly, and inhibition of protein kinase C-mediated phosphorylation. Reduced expression of S100A1 has been implicated in cardiomyopathies.
S100 proteins are localized either in the cytoplasm or the nucleus of a wide range of cells. There are at least 13 members in the S100 gene family, which are located as a cluster on chromosome 1q21.

Synaptic vesicle membrane docking and fusion is mediated by SNAREs (soluble N-ethylmaleimide-sensitive factor attachment protein receptors) located on the vesicle membrane (v-SNAREs) and the target membrane (t-SNAREs). The assembled v-SNARE/t-SNARE complex consists of a bundle of four helices, one of which is supplied by v-SNARE and the other three by t-SNARE. For t-SNAREs on the plasma membrane, the protein syntaxin supplies one helix and the protein encoded by this gene contributes the other two. Therefore, SNAP25 product is a presynaptic plasma membrane protein involved in the regulation of neurotransmitter release. The synaptosomal-associated protein (SNAP-25) is an essential component of the core complex that mediates presynaptic vesicle trafficking. Thus, SNAP-25 is directly involved in the release of neurotransmitters.

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).

Tubulin folding cofactor C (TBCC) is a member of the TBCC family. TBCC has a role in the control of centrosome and Golgi apparatus positioning, with effects on cell shape and cell migration. Cofactor C is 1 of 4 proteins (cofactors A,D,E and C) engaged in the pathway leading to properly folded b-tubulin from folding intermediates. Cofactor E attaches to the cofactor D/beta-tubulin complex; their interaction with cofactor C subsequently causes the release of beta-tubulin polypeptides which are bound to the native state.

Ribosomal Protein S20 (RPS20) encodes a ribosomal protein which is a component of the 40S subunit. RPS20, which is located in the cytoplasm, is a part of the S10P family of ribosomal proteins. RPS20 is co-transcribed with the small nucleolar RNA gene U54, which is located in its second intron. There are multiple processed pseudogenes of RPS20 dispersed through the genome as typical for genes encoding ribosomal proteins.

Rho GDP-dissociation inhibitor 1 (ARHGDIA) is a member of the RAS gene superfamily, which encodes small guanine nucleotide exchange (GTP/GDP) factors. ARHGDIA, which is localized to the cytoplasm, inhibits the dissociation of GDP from Rho proteins, thus preventing GTP from binding to and consequently activating Rho proteins. In humans, the ARHGDIA can be phosphorylated at Ser 101 by p21-activated kinase, an event that inhibits its activity and may result in positive feedback regulation of several ARHGDIA target proteins.

Osteoclasts are multinucleated cells that resorb bone and are essential for bone homeostasis. OSCAR plays crucial roles in the regulation of the innate and adaptive immune responses.Unlike the other LRC members, OSCAR expression is found specifically in preosteoclasts or mature osteoclasts. OSCAR is an important bone-specific regulator of osteoclast differentiation. Multiple alternative splicing transcript variants encodes different isoforms have been found for this gene.

Complement Factor Properdin (CFP) which is a plasma glycoprotein, is a positive regulator of the alternative complement pathway of the innate immune system. CFP binds and stabilizes the C3- and C5-convertase enzyme complexes in a feedback loop that eventually ends with formation of the membrane attack complex and lysis of the target cell. Mutations in CFP lead to 2 forms of properdin deficiency that cause high susceptibility to meningococcal infections.

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.

HER-2/neu (erbB-2) encodes an 185-kDa orphan receptor tyrosine kinase that is constitutively active as a dimer and displays potent oncogenic activity when overexpressed. Herstatin, as the product of alternative HER-2 transcript, retains intron 8.
The herstatin mRNA is expressed in normal human fetal kidney and liver, but is at reduced levels relative to p185HER-2 mRNA in carcinoma cells that contain an amplified HER-2 gene. Herstatin appears to be an inhibitor of p185HER-2, because it disrupts dimers, reduces tyrosine phosphorylation of p185, and inhibits the anchorage-independent growth of transformed cells that overexpress HER-2.

Intein is a section of a protein which can remove itself and return the remaining segment with a peptide bond. In addition, Inteins hold an endonuclease domain which takes part in Intein proliferation. Actually, various genes have unrelated intein-coding segments inserted at altered positions and they were found in all three domains of life (eukaryotes, bacteria, and archaea) and in viruses.

NDRG2 belongs to the N-myc downregulated gene family that is a part of the alpha/beta hydrolase superfamily. NDRG2 takes part in dendritic and neuronal cell differentiation and outgrowth and is found in large quantities in heart, dendritic cells, brain, salivary gland and skeletal muscle and in small quantities in kidney and liver. In Alzheimer Disease (AD)-affected patients NDRG2 is found in brain lesions and is believed to be related to the progression of AD.

Eptifibatide binds to the platelet receptor glycoprotein (GP) IIb/IIIa of human platelets and inhibits platelet aggregation. Eptifibatide is a cyclic peptide derived from a protein discovered in the venom of the southeastern pygmy rattlesnake (Sistrurus miliarus barbouri). Eptifibatide belongs to the arginin-glycin-aspartat-mimetics and reversibly binds to platelets.

DNA repair protein complementing XP-A cells, (XPA), is a member of the XPA family. XPA protein takes a part in DNA excision repair. It Inductees repair by binding to damaged sites with different affinities depending on the photoproduct and the transcriptional state of the region. Defects in XPA is the reason of xeroderma pigmentosum complementation group A (XP-A), which is infrequent human autosomal recessive disease which characterized by solar sensitivity, high predisposition for developing cancers on areas exposed to sunlight, also may cause to neurological abnormalities.

Synaptotagmin-3 (SYT3) is a member of the synaptotagmin family. SYT3 is involved in Ca(2+)-dependent exocytosis of secretory vesicles through Ca(2+) and phospholipid binding to the C2 domain or may function as Ca(2+) sensors in the process of vesicular trafficking and exocytosis.

Calbindins are Ca-binding proteins belonging to the troponin C superfamily. CALB28K/Calbindin1/CALB1 (D28K/Spot35 protein or cholecalcin, rat 261 aa; mouse 261 aa; human 261-aa, chromosome 8q21.3-q22.1) was originally described as 27-kDA induced by vitamin D in the duodenum of chicken. In mammals, it is expressed in the kidney, pancreatic islets, and brain. In brain, its synthesis is independent of vitamin D. CABP28K contains 4 active and 2 inactive EF-hand Ca-binding domains. The gene for CABP28K is clustered in the same region as carbonic anhydrase. The neurons in the brains of patients with Huntington disease are CAB28K depleted. There are two types of CaBPs: the "trigger"- and the "buffer"-CaBPs. The conformation of "trigger" type CaBPs changes upon Ca2+ binding and exposes regions on protein that interact with target molecules, thus altering their activity. The buffer-type CABP are thought to control the intracellular calcium concentration. Calbindin D-28K is found predominantly in subpopulations of central and peripheral nervous system neurons, and in certain epithelial cells involved in Ca2+ transport such as distal tubular cells and cortical collecting tubules of the kidney, and in enteric neuroendocrine cells.

GAP43 is a phosphoprotein of the presynaptic membrane that takes part in synaptic reorganization and neural development. GAP43 is found in large quantities in neuronal growth cones all through the development and axonal regeneration. Additionally, GAP43 is involved in specific regions of the normal adult nervous system and has a vital part in the conservation mechanism of long-term potentiation (LTP).