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Collapsin response mediator proteins (CRMPs) are cytosolic phosphoproteins involved in neuronal differentiation as well as axonal guidance. CRMP2 was previously shown to mediate the repulsive effect of Sema3A on axons and to participate in axonal specification. The X-ray crystal structure of murine CRMP1 was determined at 2.1 resolution and demonstrates that CRMP1 is a bilobed ‘lung-shaped’ protein forming a tetrameric assembly.

TTC32 contains 3 TPR repeats. The tetratricopeptide repeat (TPR) is a structural motif. TPR is observed in organized 3–16 motifs, which form scaffolds to mediate protein–protein interactions and frequently the assembly of multiprotein complexes. TPR-containing proteins include the anaphase-promoting complex subunits cdc16, cdc23 and cdc27, the NADPH oxidase subunit p67-phox, hsp90-binding immunophilins, transcription factors, the major receptor for peroxisomal matrix protein import PEX5, the PKR protein kinase inhibitor and mitochondrial import proteins.

SLAMF1 is a member of the immunoglobulin gene superfamily and is involved in T-cell stimulation. The SLAMF1 protein is constitutively expressed on peripheral blood memory T cells, T-cell clones, immature thymocytes, and a fraction of B cells, and is swiftly induced on naive T cells after activation. There are probably 2 modes of SLAM signaling: one in which the inhibitor SH2D1A serves as a negative regulator and another in which protein-tyrosine phosphatase 2C (PTPN11)-dependent signal transduction functions.

SOS1, also known as Gingival Fibromatosis, is a Ras & Rac guanine nucleotide exchange factor. SOS1 is comprised of a number of significant domains. The REM and CDC25 domains provide the catalytic activity of SOS1 towards Ras and the histone fold DH/PH (Dbl homology & Pleckstrin homology) domains function, in tandem, to stimulate GTP/GDP exchange for Rac. Moreover, binding of GTP activates Ras proteins, and subsequent hydrolysis of the bound GTP to GDP and phosphate inactivates signaling by these proteins. GTP binding can be catalyzed by guanine nucleotide exchange factors for RAS, and GTP hydrolysis can be enhanced by GTPase-activating proteins.

ZMAT3 is a protein with a nuclear localization signal and 3 zinc finger domains. The mRNA and the protein of this gene are upregulated by wildtype p53. When overexpressed, ZMAT3 can produce tumor cell growth, indicating that ZMAT3 takes part in the p53-dependent growth regulatory pathway. Alternative splicing of ZMAT3 produce two transcript variants encoding two isoforms differing in only one amino acid.

Calumenin is a calcium-binding protein located in the endoplasmic reticulum (ER) and sarcoplasmic reticulum (SR) of mammalian tissues which plays a role in ER functions as protein folding and sorting. Calumenin belongs to a family of multiple EF-hand proteins (CERC) that include reticulocalbin, ERC-55, and Cab45 and the product of this gene. Calumenin binds 7 calcium ions having low affinity and takes part in such ER functions as protein folding and sorting.

Podocalyxin (PODXL) is a greatly glycosylated transmembrane sialoprotein in the CD34 and endoglycan family. The PODXL protein is involved in the regulation of both adhesion and cell morphology and cancer progression. PODXL functions as an anti-adhesive molecule, which retains an open filtration pathway between neighboring foot processes in the podocyte by charge repulsion. Moreover, PODXL serves as a pro-adhesive molecule, enhancing the adherence of cells to immobilized ligands, increasing the rate of migration and cell-cell contacts in an integrin-dependent manner.

STE20-Related Kinase Adaptor Alpha (STRADA) is a part of the STE- 20 like kinase family which stimulates MAPK pathways by activating MAPKKK. STRADA is an upstream activator of LKB1 and also leads the sub-cellular localization of LKB1 by fixing it in the cytoplasm. The interaction between STRADA-LKB1 leads to phosphorylation of STRADA and enhanced autophosphorylation of LKB1.

Proteasome subunit alpha type 4 (PSMA4) belongs to the peptidase T1A family, which is a 20S core alpha subunit. The proteasome is a multicatalytic proteinase complex with an extremely ordered ring-shaped 20S core structure. The core structure is comprised of 4 rings of 28 non-identical subunits; 2 rings are composed of 7 alpha subunits and 2 rings are composed of 7 beta subunits. PSMA4 is dispersed throughout eukaryotic cells at a high concentration and cleaves peptides in an ATP/ubiquitin-dependent process in a non-lysosomal pathway.

Charged multivesicular body protein 3 (VPS24/CHMP3) is a member of the vacuolar sorting protein family and function as chromatin modifying proteins. VPS24 links directly with CHMP2 and CHMP4 for the disassembly of ESCRT-III complex in an ATP-dependent manner. During HIV-1 infection, the virus uses the ESCRT-III complex to mediate budding and exocytosis of viral proteins. VPS24 overexpression strongly hinders HIV-1 release.

XIAP Associated Factor 1 (XAF1) is a protein which binds to and counteracts the inhibitory effect of a member of the IAP (inhibitor of apoptosis) protein family. IAP proteins bind to and inhibit caspases which are activated in the course of apoptosis. The ratio of IAPs and proteins which interfere with their activity, such as the XAF1 protein, influence the progress of the apoptosis signaling pathway. Additionally, XAF1 inhibits anti-caspase activity of BIRC4. XAF1 induces cleavage and inactivation of BIRC4 independent of caspase activation. Furthermore, XAF1 mediates TNF-alpha-induced apoptosis and is involved in apoptosis in trophoblast cells.

BUD31 is a member of the BUD31 (G10) family. BUD31 is a nuclear protein which contains a putative nuclear translocation sequence, an N-terminal acidic domain and a cysteine-rich C-terminal domain containing a putative Zinc-finger structure. Based on the structure of BUD31 it is suggested that BUD31 might be a nuclear regulator of transcription.

Tropomyosin beta chain isoform 2 is affiliate to the actin filament binding protein family which primarily expressed in slow, type 1 muscle fibers. Mutations in TPM2 can change the expression of other sarcomeric tropomyosin proteins, and cause cap disease, nemaline myopathy and distal arthrogryposis syndromes.

Synaptotagmin-1(SYT1) is a member of the synaptotagmin family, which contains two C2 domains. The synaptotagmins are integral membrane proteins of synaptic vesicles assumed to function as Ca(2+) sensors in the process of vesicular trafficking and exocytosis. SYT1 is the principal regulator responsible for allowing the human brain to release neurotransmitters. SYT1 may have a regulatory role in the membrane interactions during trafficking of synaptic vesicles at the active zone of the synapse. SYT1 binds acidic phospholipids with a specificity which entails the presence of both an acidic head group and a diacyl backbone. SYT1 can also bind to at least 3 additional proteins in a Ca2+-independent manner; these being neurexins, syntaxin and AP2.

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.

BP-1 gene, a member of the DLX homeobox gene family, is overexpressed in 80% of breast cancer patients, and thus represents a potential new target for diagnosis and treatment.
Members of the Dlx gene family contain a homeobox that is related to that of Distal-less (Dll), a gene expressed in the head and limbs of the developing fruit fly (Drosophila). The Distal-less (Dlx) family of genes comprises at least 6 different members, DLX1-DLX6. The DLX proteins are postulated to play a role in forebrain and craniofacial development. Three transcript variants have been described for this gene, however, the full length nature of one variant has not been described. Studies of the two splice variants revealed that one encoded isoform functions as a repressor of the beta-globin gene while the other isoform lacks that function.

BolA Homolog 1(BOLA1) is a member of the bolA/yrbA family. BolA proteins, which include the: hBolA1, hBolA2, and hBolA3, are novel non-classical secreted proteins detected with bioinformatics and molecular biology experiments. The 3 BolA fusion proteins with c-Myc tag can be secreted into the culture medium of the transfected Cos-7 cells, even though they could not be colocalized with Golgi apparatus. Also, the secretion of 3 BolA proteins could not be inhibited after BFA treatment.

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.

Coiled-Coil Domain Containing 25 (CCDC25) is a 208 amino acid protein belonging to the CCDC25 family.

Streptavidin is a tetrameric protein secreted by Streptomyces avidinii which binds firmly to biotin. Streptavidin is widely used in molecular biology through its unique high affinity for the vitamin biotin. The dissociation constant (Kd) of the biotin-streptavidin complex is about ~10-15 mol/L. The strong affinity recognition of biotin and biotinylated molecules has made streptavidin one of the most important components in diagnostics and laboratory kits. The streptavidin/biotin system has one of the biggest free energies of association of yet observed for noncovalent binding of a protein and small ligand in aqueous solution (K_assoc = 10**14). The complexes are also extremely stable over a wide range of temperature and pH.

The bone morphogenetic protein (BMP) receptors are a family of transmembrane serine/threonine kinases that include the type I receptors BMPR1A and BMPR1B and the type II receptor BMPR2. These receptors are also closely related to the receptors, ACVR1 and ACVR2. The ligands of these receptors are members of the TGF-beta superfamily. TGF-betas transduce their signals through the formation of heteromeric complexes with 2 different types of serine (threonine) kinase receptors: type I receptors of about 50-55 kD and type II receptors of about 70-80 kD. Type II receptors bind ligands in the absence of type I receptors, but they require their respective type I receptors for signaling, whereas type I receptors require their respective type II receptors for ligand binding.

BCA-1 is a CXC chemokine that is highly expressed in thesecondary lymphoid organs, such as follicles of the spleen, lymph nodes, and Peyer's patches. CXCL13 promotes the migration of B lymphocytes (compared to T cells and macrophages), by stimulating calcium influx into, and chemotaxis of, cells expressing Burkitt's lymphoma receptor 1 (BLR1). BCA1 therefore function in the homing of B lymphocytes to follicles. Human BCA-1 shares a 64% amino acid sequence similarity with the mouse protein and 23 - 34% amino acid sequence identity with other known CXC chemokines. Recombinant or chemically synthesized BCA1 is a potent chemoattractant for B lymphocytes but not T lymphocytes, monocytes or neutrophils. BLR1, a G protein-coupled receptor originally isolated from Burkitt’s lymphoma cells, has now been shown to be the specific receptor for BCA1. Among cells of the hematopoietic lineages, the expression of BLR-1, now designated CXCR-5, is restricted to B lymphocytes and a subpopulation of T helper memory cells.

Gamma-glutamylaminecyclotransferase (A2LD1) is an enzyme which converts gamma-glutamylamines to free amines and 5-oxoproline. A2LD1 demonstrates high activity toward gamma-glutamyl-epsilon-lysine, derived from the breakdown of fibrin and other proteins cross-linked by transglutaminases. A2LD1 assists in the proteolytic degradation of crosslinked fibrin by breaking down isodipeptide L-gamma-glutamyl-L-epsilon-lysine, which is a byproduct of fibrin degradation. The reaction catalyzed by the A2LD1 produces 5-oxo-L-proline and a free alkylamine.