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Heterogeneous Nuclear Ribonucleoprotein K, also known as HNRNPK, is a part of the subfamily of ubiquitously expressed heterogeneous nuclear ribonucleoproteins (hnRNPs). HNRNPK takes part in p53/TP53 reaction to DNA damage, acting at the level of both transcription activation and repression. HNRNPK is located in the nucleoplasm and has 3 repeats of KH domains which bind to RNAs.

ARL11 (ADP-ribosylation factor-like protein 11) belongs to the ARF family of the Ras superfamily of small GTPases which are known to be involved in multiple regulatory pathways altered in human carcinogenesis. ARFs are highly conserved guanine nucleotide binding proteins which enhance the ADP-ribosyltransferase activity of choleratoxin. ARFs are important in eukaryotic vesicular trafficking pathways and they have a vital role in the activation of phospholipase D (PC-PLD). ARL11 is assumed to act as a tumor suppressor which may have a role in the regulation of apoptosis.

CMC4 is a downstream 8kDa protein restricts to mitochondria which was identified by participation in some t(X;14) translocations related with mature T-cell proliferations. This region has a compound gene structure, with a common promoter and 5’ exon spliced to two different groups of 3’ exons which encode 2 separate proteins.

Ras-related protein Ral-A (RALA) is a member of the small GTPase superfamily, Ras family of proteins. RALA mediates a distinct downstream signaling pathway from Ras which facilitates cellular transformation. Furthermore, RALA is thought to be involved in various signaling cascades, including regulation of the cytoskeleton, vesicle trafficking, and endocytosis.

Intrinsic Factor is a member of the cobalamin transport protein family. It encodes a glycoprotein secreted by parietal cells of the gastric mucosa and is required for adequate absorption of vitamin B12 in the terminal ileum. Vitamin B12 is essential for erythrocyte maturation and mutations in the Intrinsic Factor may lead to congenital pernicious anemia. Upon entry into the stomach, vitamin B12 binds to one of two B12 binding proteins present in the gastric fluid. In the less acidic environment of the small intestine, these proteins dissociate from the vitamin, allowing it to bind to intrinsic factor and enter the portal circulation through a receptor in the ileal mucosa specific for the B12-intrinsic factor complex.

WW domain-binding protein 2 (WBP2) is a steroid hormone receptor coactivator, which contains 1 GRAM domain. The globular WW domain is comprised of 38-40 semiconserved amino acids shared by proteins of various functions including structural, regulatory, and signaling proteins. This domain is involved in mediating protein-protein interactions through the binding of polyproline ligands. WBP2 binds to the WW domain of Yes kinase-associated protein(YAP1) via its PY motifs.

Zinc-alpha-2-glycoprotein (ZAG) is found in body fluids such as serum, sweat, and seminal and breast cyst fluids. It is identical in amino acid sequence to tumor-derived lipid mobilizing factor (LMF), a protein associated with the dramatic loss of adipose body stores in cancer cachexia, and has been shown to stimulate lipolysis by adipocytes in vivo and in vitro. A role for ZAG has been proposed in the regulation of body weight, and age-dependent changes in genetically influenced obesity, and also it regulates melanin production by normal and malignant melanocytes. It has also recently been classified as a novel adipokine in that it is produced by both white and brown fat adipocytes and may act in a local autocrine fashion in the reduction of adiposity in cachexia. Controlling ZAG/LMF's activity could be life-saving in the management of certain cancers and other cachexiainducing conditions, and its possible normal role in body fat store homeostasis is deserving of understanding in its own right. ZAG exhibits a class I major histocompatibility complex (MHC) fold but is a soluble protein rather than being anchored to plasma membranes and does not associate with alpha-2-microglobulin in humans. Like antigen-presenting MHC class I proteins, ZAG has an open apical groove, and X-ray crystallography of human derived ZAG revealed an unidentifiable electron density in a similar position to that occupied by antigenic peptides in classical MHC proteins and glycolipids in isoforms of CD1. This presumptive ligand is not a peptide, and the groove is too small to hold a glycolipid such as is presented by CD1 isoforms. By analogy with all other MHC class I-related proteins that have an open apical groove [some do not ], occupancy by a ligand is probably crucial to ZAG's biological function. Despite all of the structural and biochemical evidence that ZAG binds a ligand, none has so far been found by extraction from protein isolated from biological fluids. This difficulty could be because the ligand is labile, heterogeneous, or readily lost during purification procedures. Knowing more about how ZAG interacts with the compounds it has been found to bind, both natural and artificial, will inform searches for the elusive ligand(s) and its/their role in ZAG's signaling function.

SEPT5 is a member of the septin gene family of nucleotide binding proteins which were initially defined in yeast as cell division cycle regulatory proteins. Septins are extremely conserved in yeast, Drosophila, and mouse and seem to regulate cytoskeletal organization. Interference of septin function disrupts cytokinesis and results in high multinucleate or polyploid cells.

FABP multigene family has almost 20 known members. FABPs are divided into 3 different types: hepatic, intestinal and cardiac which form 14-15 kDa proteins that take part in the uptake, intracellular metabolism and/or transport of long-chain fatty acids. FABPs are involved in the modulation of cell growth and proliferation. Intestinal FABP (FABP2) gene has a polymorphism at codon 54 that identified an alanine-encoding allele and a threonine-encoding allele. Thr-54 protein is associated with increased fat oxidation and insulin resistance. High serum levels of FABP2 is ulcerative colitis indicates ileitis. FABP2 is has part in triglyceride-rich lipoprotein synthesis. FABP2 binds saturated long-chain fatty acids with a high affinity, but binds with a lower affinity to unsaturated long- chain fatty acids. FABP2 helps maintain energy homeostasis by functioning as a lipid sensor.

TAR DNA Binding Protein (TARDBP) was initially recognized as a transcriptional repressor which binds to chromosomally integrated TAR DNA and represses HIV-1 transcription. In addition, TARDBP has been detected in individuals diagnosed with chronic traumatic encephalopathy as well, which is a condition that often imitates ALS andhas been related with athletes who have experienced multiple concussions and other types of head injury.TARDBP has been shown to bind both DNA and RNA, it has multiple functions in transcriptional repression, pre-mRNAsplicing and translational regulation.

CETN1 is an EF-hand type Ca2+-binding protein. CETN1 is localized to the centrosome of interphase cells, and reorganizes the region of the spindle poles during mitosis, reflecting the dynamic behavior of the centrosome during the cell cycle. CETN1 has a vital part in the determination of centrosome position and isolation, and in the course of microtubule separating.

Folate Receptor 1, also known as FOLR1, is a part of the folate receptor family whose members bind folic acid. FOLR1 binds to folate and reduced folic acid derivatives and facilitates transfer of 5-methyltetrahydrofolate and folate analogs into the cells. FOLR1 is either attaches to membranes through a glycosyl-phosphatidylinositol linkage or exists in a soluble form. FOLR1 is also needed for embryonic development and normal cell proliferation.

CRH is a powerful stimulator of synthesis and secretion of preopiomelanocortin-derived peptides. CRH concentration in the human peripheral circulation is usually low. The concentration rises during pregnancy and fall back quickly after parturition. Maternal plasma CRH most likely originates from the placenta. Human plasma has a CRH-binding protein that inactivates CRH and can inhibit inappropriate pituitary-adrenal stimulation in pregnancy.

Prolactin inducible protein (PIP) is a 17kDa glycoprotein existing in human seminal plasma. PIP is synthesized as a 146 amino acid long polypeptide exhibiting high sequence similarity with mouse submaxillary gland with a single glycosylation site. The precise biological functions of PIP are still ambiguous but various functions have been assigned to PIP due its existence at high concentration in biological fluids. PIP binds to various proteins such as fibrinogen, actin, keratin, myosin and tropomyosin. PIP is also expressed in pathological conditions of the mammary gland and in some exocrine tissues, such as the lacrimal, salivary and sweat glands. Due to PIP’s association with secretory cell differentiation, it has been used in diagnostic evaluation of tumors of breast, salivary gland, and skin.

VAMP3 is present in recycling endosomes and endosome-derived vesicles. VAMP3 has been implicated in recycling of transferrin receptors to the plasma membrane, secretion of alpha-granules in platelets, recycling of T-cell receptors to the immunological synapses, and membrane trafficking during cell migration. VAMP-3 is present in human platelets and necessary for granule secretion. Synaptobrevins are the main components of a protein complex involved in the docking and/or fusion of synaptic vesicles with the presynaptic membrane. VAMP3 high homology to other VAMPs in its broad tissue distribution and subcellular localization is shown to be the human equivalent of the rodent cellubrevin. In platelets the protein resides on a compartment that is not mobilized to the plasma membrane on calcium or thrombin stimulation.

The bone morphogenetic proteins (BMPs) are a family of secreted signaling molecules that can induce ectopic bone growth. Many BMPs are part of the transforming growth factor-beta (TGFB) superfamily. BMPs were originally identified by an ability of demineralized bone extract to induce endochondral osteogenesis in vivo in an extraskeletal site. Based on its expression early in embryogenesis, the BMP encoded by this gene has a proposed role in early development. In addition, the fact that this BMP is closely related to BMP5 and BMP7 has lead to speculation of possible bone inductive activity.

Cysteine-rich PDZ-binding protein, also known as CRIPT, takes part in the cytoskeletal anchoring of DLG4 in excitatory synapses.

Rho-related GTP-binding protein RhoB (RhoB) belongs to the Rho GTP-binding protein family. RhoB facilitates apoptosis in neoplastically transformed cells after DNA damage. RhoB has a negative role in tumorigenesis since deletion causes tumor formation.

SNAPIN is involved in the neurotransmitter release process through its modulation of the sequential interactions between the SNAREs and synaptotagmin. SNAPIN is part of the SNARE complex of proteins that is needed for synaptic vesicle docking and fusion. SNAPAP is enriched in neurons and exclusively located on synaptic vesicle membrane protein. SNAPIN is also an important factor of the BLOC1 multisubunit protein complex. BLOC1 is required for normal biogenesis of specialized organelles of the endosomal-lysosomal system, such as melanosomes and platelet dense granules.

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.

CYR61 is a growth factor-inducible, immediate-early gene that has multifaceted activities in various cancers. CYR61 is a secreted, cysteine-rich, binding protein which is encoded by a growth factor-inducible immediate-early gene. Acting as an extracellular, matrix-associated signaling molecule, CYR61 promotes the adhesion of endothelial cells through interaction with integrin and enhances growth factor-induced DNA synthesis in the same cell type.

Tribbles Pseudokinase 3, also known as TRIB3, is a putative protein kinase which is induced by the transcription factor NF-kappaB. In addition, TRIB3 is a negative regulator of NF-kappaB, and can as well sensitize cells to TNF- and TRAIL-induced apoptosis. Furthermore, TRIB3 is able to negatively regulate the cell survival serine-threonine kinase AKT1. One of the diseases which are associated with TRIB3 is anoxia.

Methionine sulfoxide reductase B1 (SEPX1 or MSRB1), is a selenoprotein that contains a selenocysteine (Sec) residue at its active site. The selenocysteine is encoded by the UGA codon that usually signals translation termination. SEPX1 is a member of the methionine sulfoxide reductase B (MsrB) family, and is expressed in an assortment of adult and fetal tissues. MSRs (Methionine sulfoxide reductases) catalyze the reduction of free and protein-bound methionine sulfoxides to corresponding methionines. The oxidation of methionine by ROS creates a diastereomeric mixture of methionine-S-sulfoxide (Met-S-SO) and methionine-R-sulfoxide (Met-R-SO). Two separate enzyme families evolved for reduction of these sulfoxides, with methionine-S-sulfoxide reductase (MsrA) being stereospecific for Met-S-SO and methionine-R-sulfoxide reductase (MsrB) for Met-R-SO.

RHOV belongs to the Rho family and to the small GTPase superfamily. RHOV is a 236 aa protein which regulates the actin cytoskeleton by activating the JNK pathway. RHOV is expressed in placenta, pancreas and fetal brain and operates as a lipid anchor at the cytoplasmic side of the cell membrane.