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SKP1 is a F-box enzyme which functions as a substrate recognition component of the SCF ubiquitin ligase complex which controls the ubiquitination of proteins involved in cell cycle progression, signal transduction and transcription. SKP1 binds to proteins containing an F-box motif, such as cyclin F, S-phase kinase-associated protein 2, and other regulatory proteins involved in ubiquitin dependent proteolysis. SKP1 takes part in the control of beta-catenin levels and the activity of beta-catenin dependent TCF transcription factors. SKP1 serves as an adapter that links the F-box protein to CUL1 in the SCF complex.

ACTN1 encodes a nonmuscle, cytoskeletal, alpha actinin isoform and maps to the same site as the structurally similar erythroid beta spectrin gene. Alpha actinins belong to the spectrin gene superfamily which represents a diverse group of cytoskeletal proteins, including the alpha and beta spectrins and dystrophins. Alpha actinin is an actin-binding protein with multiple roles in different cell types. In nonmuscle cells, the cytoskeletal isoform is found along microfilament bundles and adherens-type junctions, where it is involved in binding actin to the membrane. In contrast, skeletal, cardiac, and smooth muscle isoforms are localized to the Z-disc and analogous dense bodies, where they help anchor the myofibrillar actin filaments.

Streptavidin is a tetrameric protein secreted by Streptomyces avidinii which binds firmly to biotin. Streptavidin is wilyde used in molecular biology through its unique high affinity for the vitamin biotin. The dissociation constant (Kd) of the biotin-streptavidin complex is about ~10-15 mol/L. The strong affinity recognition of biotin and biotinylated molecules has made streptavidin one of the most important components in diagnostics and laboratory kits. The streptavidin/biotin system has one of the biggest free energies of association of yet observed for noncovalent binding of a protein and small ligand in aqueous solution (K_assoc = 10**14). The complexes are also extremely stable over a wide range of temperature and pH.

CUTC belongs to the Cut family and may be involved in efflux trafficking of cuprous ion. The Cut family is linked with the copper homeostasis and involved in several vital metabolisms, such as uptake, storage, delivery, and efflux of copper. Copper which is an essential heavy metal trace element has an imperative role in cell physiology.

MAEA is a 396aa widely expressed adhesion protein which has 5 alternatively spliced isoforms. MAEA holds one CTLH domain and one LisH domain. MAEA forms a complex with F-actin, which takes part in regulating actin distribution in erythroblasts and macrophages and is known to assist in cell division and nuclear architecture. MAEA is confined with condensed chromatin at prophase, nuclear spindle poles at metaphase and in the contractile ring throughout cytokinesis phase and telophase.

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.

S100A4 is part of the S100 super-family of proteins containing 2 EF-hand calcium binding domains. S100A4 is ubiquitously overexpressed and is localized in the cytoplasm and/or nucleus. S100A4 is involved in motility, invasion, and tubulin polymerization. Chromosomal rearrangements and altered expression of the S100A4 gene have been implicated in tumor metastasis.

CTNNBIP1 binds CTNNB1 and avoids interaction between CTNNB1 and TCF (T-cell transcription factor) family members. CTNNBIP1 is a negative regulator of the Wnt signaling pathway.

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 may function in stimulation of Ca2+-dependent insulin release, stimulation of prolactin secretion, and exocytosis. Chromosomal rearrangements and altered expression of the S100A6 gene are implicated in melanoma.

SPA17 is a protein present at the cell surface. SPA17 was characterized by its participation in the binding of sperm to the zona pellucida of the oocyte. The central portion of SPA17 has carbohydrate binding motifs and likely takes part in cell-cell adhesion functions such as immune cell migration and metastasis.

NAPA is part of the SNAP (Soluble NSF Attachment Protein) family. SNAPs, acting together with SNAREs (SNAP receptors) and the N-ethylmaleimide-sensitive fusion protein (NSF), are necessary for the fusion of transport vesicles to their objective membranes in synaptic transmission, intra-Golgi transport, endosome-to-endosome fusion and transcytotic vesicles-to-plasma membrane transport. NAPA is in charge of the binding of NSF and therefore the formation of a 20S fusion particle.

Mouse S100A15 is a protein of 104 amino acids with an expected molecular weight of 12,870 Dalton having 2 EF-hand calcium binding sites. The S100A15 expression is upregulated in cultured keratinocytes stimulated to differentiate by calcium or phorbol esters. S100A15 is expressed in the skin and keratinocytes.

Myosin Binding Protein C, Cardiac (MYBPC3) is the cardiac isoform of myosin-binding protein C expressed exclusively in heart muscle. Myosin-binding protein C is a myosin-associated protein found in the cross-bridge-bearing zone (C region) of A bands in striated muscle. Regulatory phosphorylation of the cardiac isoform in vivo by cAMP-dependent protein kinase upon adrenergic stimulation may be associated with modulation of cardiac contraction. MYBPC3 gene mutations are one of the causes of familial hypertrophic cardiomyopathy. In vitro MYBPC3 binds MHC, F-actin and native thin filaments, and modifies the activity of actin-activated myosin ATPase. MYBPC3 may modulate muscle contraction or it may have a more structural role.

Calbindin 1 (CALB1) is a calcium binding protein that is a member of the troponin C superfamily. CALB1 plays a vital role in calcium regulation (including calcium transport and uptake, calcification of bone and teeth) and calcium associated signaling in neurons and transiently in embryological development. CALB1 also has a role in protecting neurons from apoptotic cell death. CALB1 buffers cytosolic calcium and may stimulate a membrane Ca2+-ATPase and a 3',5'-cyclic nucleotide phosphodiesterase. The biological function of CALB1 seems to be tied to the redox state of its five cysteine residues.
CALB1 has 4 active calcium-binding domains, and 2 modified domains that seemingly have lost their calcium-binding ability. CALB1 is expressed in neural tissues. In the brain, the CALB1 synthesis is independent of vitamin-D-derived hormones.
Disregulation of the CALB1 is associated with epilepsy, amyotrophic lateral sclerosis, Huntington's disease. The neurons in brains of Huntington disease patients are calbindin-depleted.

UBL3 - a member of the ubiquitin-like family is found in the membrane. UBL3 holds two N-glycosylation sites, a C-terminal prenylation site and a protein kinase C phosphorylation site. Even though Ubiquitin-like proteins are not directly involved in protein degradation, it seems they have several mechanistic similarities to the ubiquitin pathway.

CRP is an acute phase protein that correlates with inflammatory disease and is synthesized by hepatocytes during the acute phase response by certain cytokines (IL-1 and TNF Alpha and Beta). CRP levels increase dramatically (up to 1,000 fold) and serve as a useful marker of inflammation in such conditions as bacterial infection, rheumatoid arthritis, viral infections, transplantation rejection, meningitis, myocardial infarction, septicemia, osteomyelitis and others. CRP is also highly correlated to Serum Amyloid A levels.

DNAJB11 is a member of the evolutionarily conserved DNAJ/HSP40 family of proteins, which regulate molecular chaperone activity by stimulating ATPase activity. DNAJB11 serves as a co-chaperone for HSPA5 and binds directly to both unfolded proteins which are substrates for ERAD and nascent unfolded peptide chains, but dissociates from the HSPA5-unfolded protein complex before folding is completed.

STEAP Family Member 4 (STEAP4) is a member of the STEAP (six transmembrane epithelial antigen of prostate) family, resides in the golgi apparatus. STEAP4 act as a metalloreductase which has the ability to reduce both Fe(3+) to Fe(2+) and Cu(2+) to Cu(1+),using NAD(+) as acceptor. According to studies in mice and human it is possible that STEAP4 may involve in adipocyte development and metabolism, and also contribute to the normal biology of the prostate cell.

Ubiquitously-expressed transcript (UXT) is a member of the UXT family. UXT serves as a cofactor which modulates androgen receptor-dependent transcription, and also has a crucial role in tumor necrosis factor-induced apoptosis. UXT gene expression has a role in tumorigenesis. UXT is ubiquitous expressed: it is expressed in prostate epithelial cells, overexpressed in a number of tumor tissues. The highest levels are found in the heart, skeletal muscle, pancreas, kidney, liver, adrenal gland, peripheral blood leukocytes, lymph node, prostate, and thyroid and the lowest levels in bladder and uterus.

Protein Kinase CAMP-Dependent Catalytic Beta (PRKACB) belongs to the Ser/Thr protein kinase family and is a catalytic subunit of cAMP-dependent protein kinase. cAMP is a signaling molecule imperative for various cellular functions. cAMP activates the cAMP-dependent protein kinase, which transduces the signal by way of phosphorylation of different target proteins. The inactive kinase holoenzyme is a tetramer composed of 2 regulatory and 2 catalytic subunits. cAMP triggers the dissociation of the inactive holoenzyme into a dimer of regulatory subunits bound to 4 cAMP and 2 free monomeric catalytic subunits. PRKACB mediates cAMP-dependent signaling initiated by receptor binding to GPCRs. PKA activation regulates various cellular processes such as cell proliferation, the cell cycle, differentiation and regulation of microtubule dynamics, chromatin condensation and decondensation, nuclear envelope disassembly and reassembly, in addition to regulation of intracellular transport mechanisms and ion flux. PRKACB regulates the abundance of compartmentalized pools of its regulatory subunits via phosphorylation of PJA2 which binds and ubiquitinates these subunits, leading to their consequent proteolysis.

Ku antigen consists of two polypeptides (70 kDa and 80 kDa; the p80 subunit is occasionally called p86). The Ku heterodimer provides DNA-binding and regulatory functions to DNA-dependent protein kinase which is a central enzyme for DNA recombination processes in eucaryotic cells. The Ku protein plays important roles in multiple nuclear processes including DNA repair, V(D)J recombination, telomere maintenance, and the regulation of specific gene transcription.
Antibodies to Ku were originally reported in scleroderma-polymyositis overlap syndrome (up to 20% of patients) but have also been detectable in about 20 % of patients with primary pulmonary hypertension (as a complication of overlap), in 5-10 % of SLE and MCTD patients, and in up to 20 % of patients with primary Sj?gren's syndrome.
In IIF using HEp-2 cells, Ku-positive sera yield a dense, fine granular pattern with nucleolar staining that is typical but not specific for anti-Ku. Detection of Ku antibodies by Western blot may bear false-negative results since the main reactive epitope on the p70/p80 heterodimer is conformation-dependent.

C3 is central to the activation of all 3 pathways of complement activation. Initiation of each pathway generates proteolytic enzyme complexes which binds the target surface. These enzymes cleave a peptide bond in C3 releasing the anaphylatoxin C3a and activating C3b. Most of the C3 activated during complement activation never attaches to the surface due to its thioester reaction with water forming fluid phase C3b which is rapidly inactivated by factors H and I forming iC3b. Surface-bound C3b is necessary in all 3 pathways for efficient activation of C5 and formation of C5b-9 complexes that lyse the target cell membrane.

Growth arrest and DNA Damage-Inducible Protein (GADD45A) binds both Cdks and PCNA. GADD45A is involved in DNA replication and repair. GADD45A stimulates DNA excision repair in vitro and inhibits entry of cells into S phase. GADD45A may serve as a link between p53-dependent cell cycle checkpoint and DNA repair. The GADD45A gene belongs to a group of genes whose transcript levels are increased following stressful growth arrest conditions and treatment with DNA-damaging agents. GADD45A responds to environmental stresses by mediating activation of the p38/JNK pathway via MTK1/MEKK4 kinase. GADD45A binds to proliferating cell nuclear antigen.

ARPC5 is a 151 amino acid subunit of the Arp2/3 complex. ARPC5 is believed to have a role in maintaining the integrity of Arp2/3. ARPC5 is a substrate for MAPKAPK-2 which, via phosphorylation of ARPC5, may participate in Arp2/3 regulatory functions and remodeling of the Actin cytoskeleton.