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The Sec61 complex is the key component of the protein translocation apparatus of the ER (endoplasmic reticulum) membrane. Oligomers of the Sec61 complex construct a transmembrane channel where proteins are translocated across and incorporated into the ER membrane. This complex consists of 3 membrane proteins- alpha, beta, and gamma. The SEC61B gene encodes the beta-subunit protein. The Sec61 subunits are also detected in the post-ER compartment, suggesting that these proteins can get out of the ER and recycle back.

HNRNPC is a member of the subfamily of ubiquitously expressed heterogeneous nuclear ribonucleoproteins (hnRNPs) which are related to pre mRNAs in the nucleus and effect pre mRNA processing and other aspects of mRNA metabolism and transport. Although all of the hnRNPs are present in the nucleus, several hnRNPs travel between the nucleus and the cytoplasm. The hnRNP proteins have specific nucleic acid binding properties.

NF-kappa-B inhibitor-interacting Ras-like protein 1 (NKIRAS1) is a member of the small GTPase superfamily. NKIRAS1 is an unusual Ras-like protein which acts as a potent regulator of NF-kappa-B activity by thwarting the degradation of NF-kappa-B inhibitor beta (NFKBIB) by most signals, describing why NFKBIB is more resistant to degradation. NKIRAS1 functions by blocking phosphorylation of NFKBIB and mediating cytoplasmic retention of p65/RELA NF-kappa-B subunit. Both GTP- and GDP-bound forms block phosphorylation of NFKBIB.

SORBS3 is an SH3 domain-containing adaptor protein. The existence of SH3 domains in the SORBS3 protein have a role in its capability to attach to other cytoplasmic molecules and contribute to cystoskeletal organization, cell adhesion and migration, signaling, and gene expression. Various transcript variants encoding different isoforms are known for this gene.

SPARC, an acronym for “secreted protein, acidic and rich in cysteine”, is also known as osteonectin or BM-40. It is the founding member of a family of secreted matricellular proteins with similar domain structure. The 303 amino acid, 43 kDa protein contains a 17 aa signal sequence, an N-terminal acidic region that binds calcium, a follistatin domain containing Kazal-like sequences, and a C-terminal extracellular calcium (EC) binding domain with two EF-hand motifs. SPARC is produced by fibroblasts, capillary endothelial cells, platelets and macrophages, especially in areas of tissue morphogenesis and remodeling. SPARC shows context-specific effects, but generally inhibits adhesion, spreading and proliferation, and promotes collagen matrix formation. For endothelial cells, SPARC disrupts focal adhesions and binds and sequesters PDGF and VEGF. SPARC is abundantly expressed in bone, where it promotes osteoblast differentiation and inhibits adipogenesis.

Lactate dehydrogenase (LDH) is an enzyme(EC1.1.1.27) present in a wide variety of organisms, including plants and animals.
A tetrameric enzyme that catalyses the interconversion of pyruvateand lactate with concomitant interconversion of NADH and NAD+. At high concentrations of pyruvate, the enzyme exhibits feedback inhibition and the rate of conversion of pyruvate to lactate is decreased. In vertebrates, genes for three different subunits (LDH-A, LDH-B and LDH-C) exist.

Chromogranin-A Isoform 1 Preproprotein or CHGA is part of the neuroendocrine secretory proteins of the chromogranin/secretogranin family. CHGA is a precursor of numerus enzymes such as pancreastatin, catestatin, vasostatin-1,vasostatin-2, and parastatin. The protein acts as a negative regulator the neuroendocrine activity of autocrine or nearby cells (paracrine). CHGA causes further production of secretory granules that contains insulin in pancreatic islet beta cells.

PTEN, a tumor suppressor, has been implicated in a large number of human tumors and is conserved from humans to worms. PTEN has a tensin like domain and a catalytic domain similar to that of the dual specificity protein tyrosine phosphatases. Characterization of PTEN protein showed that it is a phosphatase that acts on proteins and on 3-phosphorylated phosphoinositides, and can therefore modulate signal transduction pathways that involve lipid second messengers. In contrast to most of the protein tyrosine phosphatases, PTEN preferentially dephosphorylates phosphoinositide substrates. PTEN negatively regulates intracellular levels of phosphatidylinositol-3,4,5-trisphosphate in cells and acts as a tumor suppressor by negative regulation of AKT/PKB signaling pathway. Recent results indicate that at least part of its role is to regulate the activity of the serine/threonine kinase AKT/PKB, and thus influence cell survival signaling.

Coatomer Protein Complex SubunitEpsilon, also known as COPE is an epsilon subunit of coatomer protein complex. Coatomer is a cytosolic protein complex which binds to dilysine motifs and reversibly links with Golgi non-clathrin-coated vesicles. COPE is necessary forbudding from Golgi membranes, and is also essential for the retrograde Golgi-to-ER transport of dilysine-taggedproteins. Coatomer complex contain at least the alpha, beta, beta', gamma, delta, epsilon and zeta subunits. Alternatively spliced transcript variants encoding dissimilar isoforms have been identifiedfor COPE.

Vimentin expression in human malignant glioma cells depends on cellular density, algorithms of drug delivery and chemo/radio treatment. Vimentin and detyrosinated microtubules provide structural support for the extensive microtentacles observed in detached tumor cells and a mechanism to promote successful metastatic spread. Primary colorectal carcinomas display aberrant expression of vimentin, and have activated Notch and TGFbeta signaling pathways. Vimentin is a strong arterial substrate for transglutaminases. Transglutaminase-mediated vimentin dimerization results in a novel unifying pathway by which vasodilatory and remodeling responses may be regulated. Ablation of vimentin expression inhibits migration and invasion of colon and breast cancer cell lines. Vimentin is the main intermediate filament protein in mesenchymal cells and is therefore of value in the differential diagnosis of undifferentiated neoplasms.

HPRT1 has a main part in the generation of purine nucleotides through the purine salvage pathway. HPRT1 primarily functions to salvage purines from degraded DNA to renewed purine synthesis. Therefore, it performs as a catalyst in the reaction between guanine and phosphoribosyl pyrophosphate to form GMP.

SELPLG glycoprotein functions as a high affinity counter-receptor for the cell adhesion selectin molecules (P, E and L) located in stimulated T lymphocytes and myeloid cells. SELPLG binds leukocytes to activated platelets or endothelia expressing selectins, a vital role in leukocyte trafficking throughout inflammation. In order to have a high-affinity binding activity SELPLG needs two post-translational modifications, tyrosine sulfation and the addition of the sialyl Lewis x tetrasaccharide (sLex) to its O-linked glycans. Polymorphisms and abnormal expression of SELPLG are linked to defects in the innate and adaptive immune response. Alternate splicing results in multiple transcript variants.

Once a cluster of cancer cells reaches a diameter of about 1–2 mm, it must develop a blood supply in order to grow larger. Given that diffusion is no longer adequate to supply the cancerous cells with oxygen and nutrients and to remove wastes. Therefore, these cells secrete substances that promote the formation of new blood vessels (angiogenesis), which are vital for the growth and persistence of solid tumors and their metastases.
The production of several angiogenic factors (FGF-a, FGF-b, VEGF and VPF) is upregulated by tumors in order to stimulate angiogenesis. However, numerous malignant tumors also generate inhibitors of angiogenesis which include angiostatin and thrombospondin. The angiogenic phenotype is basically the end result of a net balance between the positive and negative regulators of neovascularization mentioned above. Endostatin’s role is to inhibit endothelial proliferation, therefore it is an effective angiogenesis inhibitor.

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.

TFPI is a protease inhibitor which controls the tissue factor (TF)-dependent pathway of blood coagulation. The coagulation process starts with the creation of a factor VIIa-TF complex, that proteolytically triggers additional proteases (factors IX and X) and eventually results in a fibrin clot. TFPI inhibits the activated factor X and VIIa-TF proteases in an autoregulatory loop. TFPI is glycosylated and predominantly located in the vascular endothelium and plasma in both free forms and complexed with plasma lipoproteins. A number of alternatively spliced transcript variants of this gene have are known, however the full-length nature of several of these variants were not yet established.

Anaphase-promoting complex subunit 13 (ANAPC13) is a component of the anaphase promoting complex, which is a large ubiquitin-protein ligase that controls cell cycle progression by regulating the degradation of cell cycle regulators such as B-type cyclins. The ANAPC13 protein is evolutionarily conserved and is essential for the integrity and ubiquitin ligase activity of the anaphase promoting complex.

Nectin-1, also referred to as ED4, is a poliovirus receptor- related 1 protein is a part of the Nectin family. Nectin-1 endorses cell-cell contacts by forming homophilic or heterophilic trans-dimers. Heterophilic interactions among PVRL1/nectin-1 & PVRL4/nectin-4 and among PVRL1/nectin-1 & PVRL3/nectin-3 have been found. Nectin-1 acts as an entry receptor for herpes simplex virus & pseudorabies virus as well. Likewise, Neurite outgrowth-promoting activity has been shown by Nectin-1.

P4HB is a multifunctional and highly abundant enzyme that is part of the protein disulfide isomerase family. When present as a tetramer consisting of two alpha and two beta subunits, P4HB has a role in hydroxylation of prolyl residues in preprocollagen. P4HB is a disulfide isomerase containing two thioredoxin domains that catalyze the formation, breakage and rearrangement of disulfide bonds.

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.

CCDC101 is known as a subunit of the SAGA (Spt-Ada-Gcn5 acetyltransferase) histone acetyltransferase complex in Saccharomyces cerevisiae. CCDC101 is conserved from yeast to humans.

Beta-Glucocerebrosidase, also known as GBA is amember of the glycosyl hydrolase 30 family. GBA is a lysosomal enzyme which requires a signal peptide for transport across the membrane of the rough endoplasmic reticulum as well as glycosylation for transport into lysosomes. Furthermore, Gaucher disease is caused by a deficiency in the activity of the enzyme glucocerebrosidase.

REG protein was shown to be stimulated during the regeneration of pancreatic islets. Since then, many Reg-related proteins have been identified in humans and other animals. In human, the four REG family genes, i.e., REG 1 alpha, REG 1 beta, REG-related sequence (RS) and HIP/PAP, have so far been isolated. These Reg-related proteins are classified into four subfamilies according to their amino-acid sequences, but they share a similar structure and physiological function. Reg protein is a growth factor for pancreatic beta cells and also suggests that the administration of Reg protein could be used as another therapeutic approach for diabetes mellitus. Human REG cDNA which encodes a 166-amino acid protein with a 22-amino acid signal peptide. The amino acid sequence of human REG protein has 68% homology to that of rat Reg protein.

Renin is a highly specific endopeptidase which generates angiotensin I from angiotensinogen in the plasma. angiotensin I is an important regulator of blood pressure and electrolyte balance. Renin initiates a cascade of reactions that produce an elevation of blood pressure and increased sodium retention by the kidney.