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TNFSF15 is a cytokine that belongs to the tumor necrosis factor (TNF) ligand family. This protein is abundantly expressed in endothelial cells, but is not expressed in either B or T cells. The expression of TNFSF15 is inducible by TNF and IL-1 alpha. This cytokine is a ligand for receptor TNFRSF25 and decoy receptor TNFRSF21/DR6. It can activate NF-kappaB and MAP kinases, and acts as an autocrine factor to induce apoptosis in endothelial cells. TNFSF15 is also found to inhibit endothelial cell proliferation, and thus may function as an angiogenesis inhibitor. An additional isoform encoded by an alternatively spliced transcript variant has been reported but the sequence of this transcript has not been determined.

RPA-interacting protein isoform d (RPAIN) is a single-stranded-DNA binding protein which participates in various eukaryotic DNA processes such as replication, repair and recombination. RPAIN interacting protein has been indicated as an adapter protein that is involved in RPA nuclear import instead of the prototypical importin proteins that normally mediate nuclear import. RPAIN is mainly expressed in pancreas, kidney, muscle, liver, lung, placenta, brain, heart, leukocytes, colon, intestine, ovary, testis, prostate, thymus and spleen.

CINP is a member of the CINP family. CINP cooperates with the components of the replication complex and 2 kinases, CDK2 and CDC7, to provide a working and physical link between CDK2 and CDC7 throughout the firing of the origins of replication.

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.

Snail homolog 1 (SNAI1) is involved in induction of the epithelial to mesenchymal transition (EMT), formation and maintenance of embryonic mesoderm, growth arrest, survival and cell migration. SNAI1 binds to 3 E-boxes of the E-cadherin gene promoter and represses its transcription. The nuclear protein encoded by SNAI1 is structurally identical to the Drosophila snail protein, and is considered as well to be vital for mesoderm formation in the developing embryo. At least two variants of a similar processed pseudogene have been found on chromosome 2.Among the diseases associated with SNAI1 are waardenburg syndrome type iid, and inappropriate adh syndrome.

Complement C5 is cleaved into C5a and C5b and is activated by all 3 pathways of complement activation. Each pathway of complement activation generates proteolytic enzyme complexes which binds to the target surface. These enzymes cleave a peptide bond in the larger alpha chain of C5 releasing the highly potent anaphylatoxin C5a and activating C5b. C5a has an imperative role in chemotaxis and C5b forms the 1st part of the complement membrane attack complex. Complement C5 is the 5th component of complement, which plays a central role in inflammatory and cell killing processes.

Epidermal growth factor has a profound effect on the differentiation of specific cells in vivo and is a potent mitogenic factor for a variety of cultured cells of both ectodermal and mesodermal origin. The EGF precursor is believed to exist as a membrane-bound molecule which is proteolytically cleaved to generate the 53-amino acid peptide hormone that stimulates cells to divide. EGF stimulates the growth of various epidermal and epithelial tissues in vivo and in vitro and of some fibroblasts in cell culture.

Complement Component C5a (C5a) is involved in the complement system and it is encoded by the C5 gene in human. Complement C5 is cleaved into C5a and C5b. C5a has an imperative role in chemotaxis and C5b forms the 1st part of the complement membrane attack complex. Complement C5 is the 5th component of complement, which plays a central role in inflammatory and cell killing processes. C5a protein is composed of alpha and beta polypeptide chains, which are linked by a disulfide bridge. An activation peptide, C5a, which is an anaphylatoxin, which has potent spasmogenic and chemotactic activity, is derivative from the alpha polypeptide via cleavage with a convertase. The C5b macromolecular cleavage product forms a complex with the C6 complement component, and this complex is the basis for creation of the membrane attack complex, which includes supplementary complement components.

Thyroglobulin (TG) represents one of the main autoantigenic targets in autoimmune thyroid disease of humans. TG is a large globular dimeric glycoprotein with a total molecular weight of 660 kDa, which occupies a key precursor role in the biosynthesis of the thyroid hormones. Approximately 75% of the total protein content of the thyroid follicle consists of TG. The thyroid gland uses the Thyroglobulin in order to produce the thyroid hormones thyroxine (T4) and triiodothyronine (T3). Thyroglobulin is produced by the thyroid epithelial cells (thyrocytes) which form spherical follicles. Thyroglobulin is subsequently secreted and stored in the follicular lumen.
Patients with Hashimoto's thyroiditis or Graves' disease, frequently develop antibodies against Thyroglobulin. Tg-specific antibodies help in the diagnosis of the above diseases, however they also may be present in apparently healthy euthyroid individuals. Blood Thyroglobulin levels can be used as a tumor marker for certain kinds of thyroid cancer, and the may also be elevated in cases of Graves' disease.

40S ribosomal protein S5 (RPS5) is a ribosomal protein, which is a member of the ribosomal protein S7P family.Ribosomes, which are the organelles that catalyze protein synthesis, composed of a small subunit and a large subunit that comprise of over 80 distinct ribosomal proteins. RPS5 is a 204 amino acid component of the 40S complex. RPS5 proteins exist as multiple processed pseudogenes which are scattered throughout the genome. RPS5 is expressed at varying amounts in colorectal cancer cells, proposing a possible role in carconigenesis.

TOR1A which is a member of the AAA family of adenosine triphosphatases (ATPases) is associated to the Clp protease/heat shock family and is expressed highly in the substantia nigra pars compacta.TOR1A functions as a molecular chaperone assisting in the suitable folding of secreted and/or membrane proteins. Mutations in TOR1A result in the autosomal dominant disorder, torsion dystonia one.

Regulator of G-protein signaling 5 (RGS5) binds directly to activated G alpha subunits and act as GTPase-activating proteins (GAPs) in order to weaken and/or modulate hormone and neurotransmitter receptor-initiated signaling by both G alpha-GTP and G beta gamma. Vascular endothelial cells express the RGS protein RGS5, where it correlates with capillary morphogenesis, consequently rendering it a candidate gene involved in capillary growth, angiogenesis, and also possibly the pathophysiology of stroke.

GNRH1 also known as Luteinising-hormone releasing hormone (LHRH), is a peptide hormone responsible for the release of FSH and LH from the anterior pituitary. GNRH1 is synthesized and released by the hypothalamus.
At the pituitary, GNRH1 stimulates the synthesis and secretion of the follicle-stimulating hormone (FSH) and luteinizing hormone (LH). These processes are controlled by the size and frequency of GNRH1 pulses, as well as by feedback from androgens and estrogens. Low requency GNRH1 pulses lead to FSH release, whereas high frequency GNRH1 pulses stimulate LH release.
There are differences in GNRH1 secretion between males and females. In males, GNRH1 is secreted in pulses at a constant frequency, but in females the frequency of the pulses varies during the menstrual cycle and there is a large surge of GNRH1 just before ovulation.
GNRH1 secretion is pulsatile in all vertebrates, and is necessary for correct reproductive function. Thus, a single hormone, GNRH1, controls a complex process of follicular growth, ovulation, and corpus luteum maintenance in the female, and spermatogenesis in the male.

Family with Sequence Similarity 3, Member A (FAM3A) is a member of the FAM3 family along with FAM3B (Pander) protein which induces apoptosis of pancreatic alpha and beta cells. FAM3A is a cytokine-like protein, which is expressed in almost all tissues such as the testis, pancreas, adrenal, placenta, brain, fetal brain, liver, kidney, skeletal muscle and the heart. FAM3A gene expression may be regulated by peroxisome proliferator-activated receptor gamma, and the FAM3A protein might be involved in the regulation of glucose and lipid metabolism. Although the function of the FAM3A protein has been unclear until now, it may act as a defensin against invading fungal microorganisms.

Mitochondrial Ribosomal Protein L48, also known as MRPL48, is a mammalian mitochondrial ribosomal protein which assists in protein synthesis within the mitochondrion. Mitochondrial ribosomes, mitoribosomes, consist of a small 28S subunit and a large 39S subunit. They include an estimated 75% protein to rRNA composition while comparing to prokaryotic ribosomes, where this ratio is reversed.An additional dissimilarity between mammalian mitoribosomes & prokaryotic ribosomes is that the latter contain a 5S rRNA. Between different species, the proteins containing the mitoribosome differ very much in sequence, as well as in biochemical properties from time to time, which prevents easy recognition through sequence homology. MRPL48 encodes a 39S subunit protein. A pseudogene corresponding to MRPL48 is found on chromosome 6p.

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.

Ribosomal Protein L5, also known as RPL5 is a part of the ribosomal protein L18P family. RPL5 which binds 5S RNA is necessary for rRNA maturation and structure of the 60S ribosomal subunits.

RGS2 belongs to the RGS family which are regulatory molecules that act as GTPase activating proteins for G alpha subunits of heterotrimeric G proteins. RGS2 inhibits signal transduction by increasing the GTPase activity of G protein alpha subunits and as a result driving them into their inactive GDP-bound form.

Retinitis pigmentosa 9 (RP9) is assumed to be a target protein for the PIM1 kinase. The RP9 protein may have some roles in B-cell proliferation in association with PIM1. RP9 can be bound and phosphorylated by the protooncogene PIM1 product, a serine/threonine protein kinase. RP9 localizes in nuclear speckles containing the splicing factors, and has a part in pre-mRNA splicing. RP9 gene mutations result in autosomal dominant retinitis pigmentosa-9.

Peroxisomal Biogenesis Factor 26 (PEX26) which is a part of the peroxin-26 gene family is probably required for protein import into peroxisomes. PEX26 attaches PEX1 and PEX6 to peroxisome membranes to form heteromeric AAA ATPase complexes needed for the import of proteins into peroxisomes. Deficiencies in this gene are the cause of peroxisome biogenesis disorder complementation group 8. PBD is a group of peroxisomal disorders evolving from a failure of protein import into the peroxisomal membrane or matrix.

Docking Protein 4(DOK4) is a member of the DOK family. DOK proteins are enzymatically inert adaptor or scaffolding proteins. The DOK proteins present a docking platform for the compilation of multimolecular signaling complexes. DOK4 serves in RET-mediated neurite outgrowth and has a positive role in activation of the MAP kinase pathway. DOK4 is a putative link with downstream effectors of RET in neuronal differentiation. DOK4 is involved in the regulation of the immune response induced by T-cells.

Family with Sequence Similarity 84, Member B (FAM84B) coprecipitated with a downstream effector of RAS, CRAF. Binding of FAM83B with CRAF interrupted CRAF/14-3-3 interactions and increased CRAF membrane localization, causing elevated MAPK and mammalian target of rapamycin (mTOR) signaling. FAM84B is an oncogene and possibly represents a new target for therapeutic intervention.

EFNA1 belongs to the ephrin (EPH) family. The EPH subfamily is the biggest group of receptor protein kinases and they take part in vital nervous system function and development.

PFDN6 is a subunit of the heteromeric prefoldin complex that chaperones developing actin and alpha- and beta-tubulin chains until they are transferred to the cytosolic chaperonin containing TCP1 (CCT) complex. PFDN6 binds specifically to cytosolic chaperonin (c-CPN), transfers target proteins to it and bind to developing polypeptide chain to promote folding in a setting where there are many competing pathways for nonnative proteins.