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The La protein is a 47 kDa polypeptide that frequently acts as an autoantigen in systemic lupus erythematosus and Sjogren's syndrome patients. La is involved in various aspects of RNA metabolism, including binding and protecting 3-prime UUU(OH) elements of newly RNA polymerase III - transcribed RNA, processing 5-prime and 3-prime ends of pre-tRNA precursors, acting as an RNA chaperone, and binding viral RNAs linked to hepatitis C virus. It occurs in both the nucleus and the cytoplasm, where it assumes different roles. In the nucleus, La protein facilitates the production of tRNAs, acting as an RNA polymerase III (RNAP III) transcription factor by attaching to the U-rich 3'UTR of nascent transcripts, aiding in their folding and maturation. In the cytoplasm, La protein facilitates the translation of specific mRNAs, acting as a translation factor. As an RNA binding protein (RBP), La protein associates with subsets of mRNAs which contain a 5'-terminal oligopyrimidine (5'TOP) motif known to direct protein synthesis. The binding of La protein to particular classes of RNA molecules regulates their downstream processing, guards them from endonuclease digestion, and organizes their export from the nucleus. La/SS-B appears to be readily disposed to proteolysis, which results in many smaller (42kD, 320, and 270) nevertheless still immunoreactive polypeptides. La/SS-B antigen is strongly conserved across species. Anti-La/SS-B autoantibodies were originally found as precipitating autoantibodies in sera of Sjogren's Syndrome patients and referred to as SjT. Anti-La/SS-B precipitins are most frequently found in Sjogren's Syndrome, Systemic Lupus Erythematosus (SLE) and Subacute Cutaneous Lupus. Also, there seems to be a correlation between anti-La/SS-B and the absence of nephritis in SLE patients.

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.

SIL1 is localized to endoplasmic reticulum (ER). SIL1 is an N-linked glycoprotein with an N-terminal ER targeting sequence, 2 putative N-glycosylation sites, and a C-terminal ER retention signal. SIL1 acts as a nucleotide exchange factor for another unfolded protein response protein. Mutations in SIL1 are linked to Marinesco-Sjogren syndrome.

SNRPE facilitates the cytoplasmic construction of the UsnRNPs by binding to a conserved Sm site on UsnRNA and forming a stable snRNP core complex. While a core protein to UsnRNP, the SNRPE connects with the entire U family of snRNAs including U1–U6. In addition, SNRPE interacts with DDX20 and Small nuclear ribonucleoprotein polypeptide F.

Synaptotagmin-4 (SYT4) is a part of the synaptotagmin proteins family. Synaptotagmins are a large gene family of synaptic vesicle type III integral membrane proteins that operate as regulators of both exocytosis and endocytosis and are involved in neurotransmitter secretion from small secretory vesicles. SYT4 is expressed in neuronal tissues, and has the highest mRNA levels in the hippocampus. The proximity of the SYT4 gene to markers of several psychiatric disorders implies an involvement of SYT4 in human disease such as pheochromocytoma, and parkinson's disease.

RERG is a 199 amino acid protein which localizes in the cytoplasm and is a member of the Ras subfamily of small GTPases. RERG is expressed in the pancreas, liver, skin, lung, brain, kidney and heart tissue. RERG is a vital mediator of diverse cell signaling pathways, including those leading to cell proliferation, cytoskeletal organization and secretion.

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.

Prolactin is a neuroendocrine hormone synthesized primarily by the pituitary gland but also a variety of other cell types including the placenta, brain and uterus. Its primary function is to promote and maintain lactation but has also been shown to have a role in breast cancer development, regulation of reproductive function and immunoregulation.

Gankyrin (proteasome 26S subunit) is a multicatalytic proteinase oncoprotein commonly overexpressed in most hepatocellular carcinomas. Proteasomes are found throughout eukaryotic cells at a high concentrations and cleave peptides in an ATP/ubiquitin-dependent process in a non-lysosomal pathway. Gankyrin interacts with S6 ATPase of the 19S regulatory particle of the 26S proteasome. Gankyrin is involved in theregulation of the phosphorylation of the retinoblastoma protein by CDK4, and to enhance the ubiquitinylation of p53 by MDM2. Gankyrin consists of 7 ankyrin repeats and is structurally similar to I kappa Bs. Gankyrin acts as a regulatory subunit of the 26s proteasome which is involved in the atp-dependent degradation of ubiquitinated proteins. Gankyrin is involved in progression of esophageal squamous cell carcinoma. gankyrin plays an oncogenic role especially in early stages of human epatocarcinogenesis. Gankyrin binds to NF-kappaB and suppresses its activity at the transcription level by modulating acetylation through SIRT1. Structural comparison between Gankyrin & p16(INK4A) identified numerous residues of gankyrin that are potentially important for CDK4 binding.

Yersinia enterocolitica is a Gram-negative bacillus-shaped bacterium, which is a member of the Enterobacteriaceae family. Y.Enterocolitica is motile at temperatures between 22-29°C, however becomes non-motile at normal human body temperature. Y. Enterocolitica infection causes the yersiniosis disease, which is an animal-borne disease occurring in humans, as well as in a various groups of animals such as cattle, deer, pigs, and birds. Yersinia enterocolitica is a heterogeneous group of strains, which are conventionally classified by bio-typing into six bio-groups on the basis of phenotypic characteristics, and by serotyping into more than 57 “O” serogroups, on the basis of their O (lipopolysaccharide or LPS) surface antigen. Five of the six biogroups (1B and 2–5) are considered as pathogens. Nevertheless, only a few of these serogroups have been linked with disease in either humans or animals. Strains which belong to serogroups O:3 (biogroup 4), O:5,27 (biogroups 2 and 3), O:8 (biogroup 1B), and O:9 (biogroup 2) are most frequently isolated worldwide from human samples. Still, the main Y. enterocolitica serogroup in many European countries is serogroup O:3 followed by O:9, whereas the serogroup O:8 is mostly detected in the United States.

DCXR catalyzes the NADPH-dependent reduction of numerous pentoses, tetroses, trioses, alpha-dicarbonyl molecules and L-xylulose. DCXR takes part in the uronate cycle of glucose metabolism. DCXR participates in the water absorption and cellular osmoregulation in the proximal renal tubules by producing xylitol, an osmolyte, thus preventing osmolytic stress from occurring in the renal tubules.

Aminoacyl-tRNA synthetases are a class of enzymes which charge tRNAs with their cognate amino acids. Asparaginyl-tRNA synthetase (NARS) is localized to the cytoplasm and is a member of the class II family of tRNA synthetases. The N-terminal domain characterizes the signature sequence for the eukaryotic asparaginyl-tRNA synthetases.

SRGN is identified as a hematopoietic cell granule proteoglycan. Proteoglycans stored in the secretory granules of various hematopoietic cells also hold a protease-resistant peptide core, and is vital for neutralizing hydrolytic enzymes. SRGN is related to the macromolecular complex of granzymes and perforin that acts as a intermediary of granule-mediated apoptosis.

Chromosome 10 Open Reading Frame 54, also known as C10ORF54 is part of the immunoglobulin superfamily. Like a transmembrane molecule, C10ORF54 is expressed in the bone on embryonic stem cells (ESCs), and on tumor cell surface as well. Accordingly, C10ORF54 supports the differentiation of ESC and ehhances BMP4 induced signaling in ESC, however C10ORF54 is also down regulated following to BMP4 exposure.

EBAG9 is a type III transmembrane protein that is primarily located in the Golgi. EBAG9 is a tumor-associated antigen that is expressed at high frequency in a variety of cancers, such as advanced breast and prostate cancers. while the EBAG9 acts to inhibit the growth of receptor-binding cells and induced apoptosis of immune cells, cancer cells may evade immune surveillance. Thus immunodetection of EBAG9 expression can be a negative prognostic indicator. EBAG9 promotes progression of bladder cancer. In rheumatoid arthritis, the deficiency of EBAG9 induces CTL infiltration through failure to evade immune attack, therefore leading to apoptosis of the synovial lining cells. EBAG9 is involved in controlling exocytosis processes. EBAG9 expression plays a role in the progression of oral squamous cell carcinoma. EBAG9 plays a specific role in premature stages of breast carcinogenesis.

SRGN is identified as a hematopoietic cell granule proteoglycan. Proteoglycans stored in the secretory granules of various hematopoietic cells also hold a protease-resistant peptide core, and is vital for neutralizing hydrolytic enzymes. SRGN is related to the macromolecular complex of granzymes and perforin that acts as a intermediary of granule-mediated apoptosis.

Killer-cell immunoglobulin-like receptors (KIRs), are a family of cell surface glycoproteins found on Natural Killer (NK) Cells, which are important cells of the immune system. They control the killing function of these cells by interacting with MHC class I molecules, which are expressed on all cell types. This interaction allows them to identify virally infected cells or tumor cells that have a distinctive low level of Class I MHC on their surface. The majority of KIRs are inhibitory, which means that their recognition of MHC suppresses the cytotoxic activity of their NK cell. Only a limited number of KIRs have the capacity to activate cells.
The KIR genes are found in a cluster on chromosome 19q13.4 within the 1 Mb leukocyte receptor complex (LRC). KIR molecules are extremely polymorphic, meaning their gene sequences differ significantly between individuals, so that different individuals have different arrays/repertoires of KIR genes.
The KIR proteins are categorized by the number of extracellular immunoglobulin domains (2D or 3D) and by whether they have a long (L) or short (S) cytoplasmic domain. KIR proteins with the long cytoplasmic domain transduce inhibitory signals upon ligand binding via an immune tyrosine-based inhibitory motif (ITIM). Whereas KIR proteins with the short cytoplasmic domain lack the ITIM motif and instead associate with the TYRO protein tyrosine kinase binding protein to transduce activating signals.
KIR2DS4 is an activating Killer Cell Ig-like Receptor (KIR, previously called p50 KIR, p50.3, cl39, or KAR-K1), which may recognize class I MHC molecules. KIR2DS4 does not inhibit the activity of NK cells.

CISD1 protein holds a CDGSH iron-sulfur domain and is known to bind a redox-active [2Fe-2S] cluster. CISD1 is restricted to the outer membrane of mitochondria and takes part in oxidation regulation.

The somatomedins, or insulin-like growth factors (IGFs), comprise a family of peptides that play important roles in mammalian growth and development. IGF1 mediates many of the growth-promoting effects of growth hormone (GH; MIM 139250). Early studies showed that growth hormone did not directly stimulate the incorporation of sulfate into cartilage, but rather acted through a serum factor, termed 'sulfation factor,' which later became known as 'somatomedin' (Daughaday et al., 1972). Three main somatomedins have been characterized: somatomedin C (IGF1), somatomedin A (IGF2; MIM 147470), and somatomedin B (MIM 193190) (Rotwein, 1986; Rosenfeld, 2003).

PRDX4 is an antioxidant enzyme that is part of the peroxiredoxin family. PRDX4 is localized to the cytoplasm. PRDX4 reduces hydrogen peroxide and alkyl hydroperoxides to water and alcohol with the use of reducing equivalents derived from thiol-containing donor molecules. PRDX4 has a regulatory part in the activation of the transcription factor NF-kappaB. PRDX4 participates in redox regulation of the cell. PRDX4 regulates the activation of NF-kappa-B in the cytosol by a modulation of I-kappa-B-alpha phosphorylation.

STYX is a member of the protein-tyrosine phosphatase family. STYX has a Gly residue instead of a conserved Cys residue in the dsPTPase catalytic loop which renders it catalytically inactive as a phosphatase. Nevertheless, the binding pocket is adequately preserved to bind phosphorylated substrates, and possibly protect them from phosphatases. STYX takes part in spermiogenesis.

HDAC2 is a member of the histone deacetylase family that performs through the construction of large multiprotein complexes and are in charge of the deacetylation of lysine residues on the N-terminal region of the core histones. HDAC2 forms transcriptional repressor complexes by relating to a diversity of proteins, like YY1- a mammalian zinc-finger transcription factor.
In addition, HDAC2 has a vital part in transcriptional regulation, cell cycle progression and developmental procedures.