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Galectins are a family of soluble b-galactoside-binding animal lectins that modulate cell-to-cell adhesion and cell-to-extracellular matrix interactions. Galectins also take part in tumor progression, pre-mRNA splicing and apoptosis. Galectin-related protein (LGALSL) is a 172 amino acid protein which holds one galectin domain. In spite of this, LGALSL does not appear to bind carbohydrates or lactose since the critical residues required for binding are not conserved.

GNMT is an enzyme that catalyzes the conversion of S-adenosyl-L-methionine with glycine to S-adenosyl-L-homocysteine and sarcosine. GNMT is located in the cytoplasm and acts as a homotetramer. Defects in the GNMT gene causes of GNMT deficiency (hypermethioninemia). GNMT affects DNA methylation by regulating the ratio of S-adenosylmethionine to S-adenosylhomocystine and is involved in the detoxification pathway in liver cells. GNMT expression is diminished in human hepatocellular carcinoma (HCC). GNMT catalyzes the methylation of glycine by using s- adenosylmethionine (adomet) to form n-methylglycine (sarcosine) with the concomitant production of s-adenosylhomocysteine (adohcy). GNMT plays an essential role in the regulation of tissue concentration of adomet and of metabolism of methionine.

PRTN3 is a polymorphonuclear leukocyte serine protease which degrades elastin, fibronectin, laminin, vitronectin, and collagen types I, III, and IV (in vitro) and causes emphysema once managed by tracheal insufflation to hamsters.

HAUS augmin-like complex subunit 1 (HAUS1) is 1 of 8 subunits of the 390kDa human augmin complex/ HAUS complex. The augmin complex is a microtubule-binding complex required in microtubule generation within the mitotic spindle and is imperative to mitotic spindle compilation. HAUS1 contributes to mitotic spindle assembly, maintenance of centrosome integrity and completion of cytokinesis as part of the HAUS augmin-like complex. HAUS1 is broadly expressed, especially in the pancreas, kidney, skeletal muscle, liver and heart. However it is weakly expressed in the lung, brain and placenta. HAUS1-depleted cells hold functional cell cycle checkpoints, but the depletion reduces the G2/M cell cycle compartment and stimulates apoptosis. The HAUS1 protein level remains constant through the cell cycle.

Resistin, a product of the RSTN gene, is a peptide hormone belonging to the class of cysteine-rich secreted proteins which is termed the RELM family, and is also described as ADSF (Adipose Tissue- Specific Secretory Factor) and FIZZ3 (Found in Inflammatory Zone). Human resistin contains 108 amino acids as a prepeptide, and its hydrofobic signal peptide is cleaved before its secretion. Resistin circulates in human blood as a dimeric protein consisting of two 92 amino acid polypeptides, which are disulfide-linked via Cys26.
Resistin may be an important link between obesity resistance. Mouse resistin, specifically produced and secreted by adipocyte, acts on skeletal muscle myocytes, hepatocytes and adipocytes themselves so that it reduces their sensitivity. They have also suggested that resistin is present at elevated levels in blood of obese mice, and is down regulated by fasting and antidiabetic drugs. Way et al., on the other hand, have found that resistin expression is severly suppressed in obesity and is stimulated by several antidiabetic drugs.
Other studies have shown that mouse resistin increases during the differentiation of adipocytes, but it also seems to inhibit adipogenesis. In contrast, the human adipogenic differentiation is likely to be associated with a down regulation of resistin gene expression.

The cytokine Macrophage migration inhibitory factor (MIF) has been identified to be secreted by the pituitary gland and the monocyte/macrophage and to play an important role in endotoxic shock. MIF has the unique property of being released from macrophages and T cells in response to physiological concentrations of glucocorticoids. The secretion of MIF is tightly regulated and decreases at high, anti-inflammatory steroid concentration.

S100A6 is a member of the S100 family of proteins containing 2 EF-hand calcium-binding motifs. S100 proteins are localized either in the cytoplasm or the nucleus of a wide range of cells. S100 proteins are involved in the regulation of a number of cellular processes such as cell cycle progression and differentiation. There are at least 13 members in the S100 gene family, which are located as a cluster on chromosome 1q21. S100A6 function in stimulation of prolactin secretion and exocytosis. Chromosomal rearrangements and altered expression of the S100A6 gene are implicated in melanoma.

S100A8 is a part of the S100 family of proteins containing 2 EF-hand calcium-binding motifs. S100 proteins are localized in the cytoplasm and/or nucleus of a broad range of cells, and participate in the regulation of cellular processes such as cell cycle progression and differentiation. S100A8 plays a role in the inhibition of casein kinase and as a cytokine. S100A8 altered expression is related with cystic fibrosis disease. S100A8 is a calcium-binding protein that has antimicrobial activity against bacteria and fungi.S100A8 is crucial for resistance towards invasion by pathogenic bacteria. S100A8 up-regulates transcription of genes that are under the control of NF-kappa-B. S100A8 plays a role in the development of endotoxic shock in response to bacterial lipopolysaccharide. S100A8 endorses tubulin polymerization and promotes phagocyte migration and infiltration of granulocytes at sites of wounding. S100A8 takes part as a pro-inflammatory mediator in acute and chronic inflammation and up-regulates the release of IL8 and cell-surface expression of ICAM1.

Sterile Alpha Motif Domain Containing 13 (SAMD13) is a putative protein interaction module which is present in various proteins involved in numerous biological processes. SAMD13 contains one SAM (sterile alpha motif) domain. The SAM domain, which spreads over around 70 residues, is found in various eukaryotic organisms. SAM domains are known to homo- and hetero-oligomerise, forming multiple self-association constructions and also binding to various non-SAM domain-containing proteins, however with a low affinity constant.

MMAB protein catalyzes the last step in the conversion of vitamin B(12) into adenosylcobalamin (AdoCbl), a vitamin B12 containing coenzyme for methylmalonyl-CoA mutase(MCM). Decreased MMAB activity leads to the inherited disorder vitamin B12 dependent methylmalonic aciduria linked to the cblB complementation group.

SAR1A is a member of the small GTPase superfamily. SAR1A is a vital component of COPII vesicle coats involved in export of cargo from the ER (Endoplasmic Reticulum). The GTPase activity of SAR1A serves as a molecular switch to control protein-protein and protein-lipid interactions which dictate vesicle budding from the ER. SAR1A, while GDP-bound interacts with the membrane-bound exchange factor Sec12 and trades its bound GDP for GTP. SAR1A is also involved in the transport from the ER to the Golgi apparatus. SAR1A is required to maintain SEC16A localization at distinct locations on the ER membrane possibly by preventing its dissociation. SAR1A-GTP-dependent compilation of SEC16A on the ER membrane creates a structured scaffold defining endoplasmic reticulum exit sites.

SAR1B is a small GTPase that functions as a homodimer. GTP-Binding Protein SAR1B (SAR1b) is involved in transport from the endoplasmic reticulum to the Golgi apparatus and also in the selection of the protein cargo and the assembly of the COPII coat complex. The SAR1B protein is activated by the guanine nucleotide exchange factor PREB. SAR1B gene defects are a cause of chylomicron retention disease (CMRD), also known as Anderson disease (ANDD).

CXC chemokine ligand 16 (CXCL16) is a type I membrane protein, which contains a non-ELR motif-containing CXC chemokine domain in its extracellular region. Human and Mouse CXCL16 share a 70% a.a. sequence similarity within their chemokine domains and 49% overall a.a. sequence identity. Functional CXCL16 can be dropped from the cell surface as an approximately 35kDa soluble protein. CXCR6 is the functional receptor for CXCL16. CXCL16 functions as a scavenger receptor on macrophages, which specifically binds to OxLDL (oxidized low density lipoprotein), proposing that CXCL16 may be involved in pathophysiology such as atherogenesis. In addition, CXCL16 induces a strong chemotactic response and calcium mobilization. CXCL16 binds to CXCR6/Bonzo.

AHCY is an enzyme that catalyzes the reversible hydrolysis of S-adenosylhomocysteine (AdoHcy) to adenosine (Ado) and L-homocysteine (Hcy). AHCY controls the intracellular S-adenosylhomocysteine (SAH) concentration that is crucial for transmethylation reactions. AHCY deficiency causes hypermethioninemia.

SDF-1 (stromal cell-derived factor-1) is small cytokine belonging to the chemokine family that is officially designated Chemokine (C-X-C motif) ligand 12 (CXCL12). It is produced in two forms, SDF-1?/CXCL12a and SDF-1?/CXCL12b, by alternate splicing of the same gene. Chemokines are characterized by the presence of four conserved cysteines, which form two disulfide bonds. The CXCL12 proteins belong to the group of CXC chemokines, whose initial pair of cysteines are separated by one intervening amino acid. CXCL12 is strongly chemotactic for lymphocytes and has been implicated as an important cell co-ordinator during development. During embryogenesis it directs the migration of hematopoietic cells from foetal liver to bone marrow. Mice which were knocked-out for CXCL12 gene were lethal before the birth or within just 1 hour of life. As another role, CXCL12a alters also the electrophysiology of neurons. CXCL12 was shown to be expressend in many tissues in mice (including brain, thymus, heart, lung, liver, kidney, spleen and bone marrow).
The receptor for this chemokine is CXCR4, which was previously called fusin. This CXCL12-CXCR4 interaction used to be considered exclusive (unlike for other chemokines and their receptors), but recently it was suggested that CXCL12 is also bound by CXCR7 receptor.
The gene for CXCL12 is located on human chromosome 10. In human and mouse both CXCL12 and CXCR4 show high identity of sequence: 99% and 90%, respectively.

SHC1 is a member of the SH2 domain family. SHC1 is vital to the regulation of apoptosis and drug resistance in mammalian cells. SHC1 is a signaling adapter which links activated growth factor receptors to signaling pathway. SHC1 is found in neural stem cells but not in mature neurons.

SLAM family member 6 (SLAMF6) is a member of the SLAM family of immune cell receptors. SLAMF6 is a unique receptor on T cells which, when triggered potentiates T cell expansion in a CD28-independent manner. SLAMF6 has a high expression on NK-, T-, and B cells. SLAMF6 exhibits homotypic interactions and can connect with adaptor molecules such as SAP to alter immune cell function.

Arylsulfatase G (ARSG) is a member of the sulfatase enzyme family. Sulfatases are enzymes which hydrolyze sulfate esters from sulfated steroids, carbohydrates, proteoglycans, and glycolipids. Sulfatases are involved in hormone biosynthesis, modulation of cell signaling, and degradation of macromolecules. The ARSG protein exhibits arylsulfatase activity at acidic pH, as is characteristic of lysosomal sulfatases. The Arylsulfatase G enzyme localizes in the lysosomes. ARSG is inhibited by phosphate, which forms a covalent bond with the active site 3-oxoalanine. Arylsulfatase G is widely expressed, having very low expression in the brain, lung, heart and skeletal muscle.

a-Synuclein (amino acids 1-140), an acidic neuronal protein of 140 amino acids, is extremely heat-resistant and is natively unfolded with an extended structure primarily composed of random coils. a-synuclein has been suggested to be implicated in the pathogenesis of Parkinson’s disease and related neurodegenerative disorders, and more recently, to be an important regulatory component of vesicular transport in neuronal cells. Moreover, recent studies have shown that a-synuclein has chaperone activity and that this activity is lost upon removing its C-terminal acidic tail (amino acids 96-140).

Neurotensin (NTS) is a common precursor for 2 peptides, neuromedin N and neurotensin. Neurotensin is a secreted tridecapeptide, which is generally distributed throughout the central nervous system, and may serve as a neurotransmitter or a neuromodulator. NTS is involved in the maintenance of gut structure and function, and in the regulation of fat metabolism. Tissue-specific processing may initiate the formation in some tissues of larger forms of neuromedin N and neurotensin. The large forms may embody more stable peptides which are also biologically active.

STC2 is a homodimeric glycoprotein that is expressed in a wide variety of tissues and may have autocrine or paracrine functions. The encoded protein has 10 of its 15 cysteine residues conserved among stanniocalcin family members and is phosphorylated by casein kinase 2 exclusively on its serine residues. Its C-terminus contains a cluster of histidine residues which may interact with metal ions. The protein may play a role in the regulation of renal and intestinal calcium and phosphate transport, cell metabolism, or cellular calcium/phosphate homeostasis. Constitutive over expression of human stanniocalcin 2 in mice resulted in pre- and postnatal growth restriction, reduced bone and skeletal muscle growth, and organomegaly. Expression of this gene is induced by estrogen and altered in some breast cancers.

Alpha-parvin (PARVA) belongs to the parvin family of actin-binding proteins. PARVA has a role in the regulation of cell adhesion, cytoskeleton organization, motility and survival as well as in ciliogenesis. Parvins are related with focal contacts and contain calponin homology domains which connect to actin filaments. PARVA is extensively expressed, with the highest levels in heart, skeletal muscle, kidney and liver.

SYT13 belongs to the great synaptotagmin protein family which contain 2 domains: cytoplasmic C terminus with two tandem C2 domains (C2A and C2B) and extracellular N-terminal transmembrane domain. Synaptotogmin family members have dissimilar biochemical properties and developmental profiles, and patterns of tissue distribution. Additionally, Synaptotogmins formulate homo- and heteromeric complexes with each other. Synaptotagmins operate as membrane traffickers in multicellular organisms.

Calmodulin Like 3 (CALML3) is a member of the calmodulin family and contains 4 EF-hand domains. The CALML3 protein may be similar to that of genuine calmodulin and may in fact compete with calmodulin by binding, with different affinities, to cellular substrates. CALML3 protein is expressed in normal mammary, prostate, cervical, and epidermal tissues.