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Microtubule-associated protein tau (MAPT or Tau) is a protein that stabilizes microtubules. MAPT is abundant in neurons in the central nervous system and is less common elsewhere. When MAPT is defective, and no longer stabilizes microtubules properly, it can result in dementias, such as Alzheimer's disease.

Recoverin is a member of the recoverin family of neuronal calcium sensors. Recoverin is a heterogeneously acylated calcium-binding and intracellular signal transduction 23kDa protein in the photoreceptor cells of retina. Recoverin contains four EF-hands, of which two bind Ca. Ca-induced extrusion of the acyl group from a hydrophobic cleft in the protein drives the translocation of recoverin from solution to the disc membrane. Recoverin may prolong the termination of the phototransduction cascade in the retina by blocking the phosphorylation of photo-activated rhodopsin. Recoverin plays a key role in the inhibition of rhodopsin kinase, a molecule that regulates the phosphorylation of rhodopsin. This in due course controls the ability of the eye to adapt to, and recover from, exposure to the presence of light. Recoverin is a detectable serologic protein that is expressed in patients with cancer-associated retinopathy, a paraneoplastic syndrome.

Cytohesin 2 (CYTH2) is an ARF-1 guanine nucleotide exchange factor (GEF). ARF (ADP ribosylation factor) proteins are a part of a group within the RAS superfamily and bindes GTP-b proteins central to the process of vesicle budding. CYTH2 promotes guanine-nucleotide exchange on ARF1, ARF3 and ARF6. Furthermore, CYTH2 promotes the activation of ARF factors through replacement of GDP with GTP. The protein encoded by CYTH2 is a member of the PSCD family. Members of PSCD family appear to mediate the regulation of protein sorting and membrane trafficking. The cell membrane form, in association with ARL4 proteins, recruits ARF6 to the plasma membrane.

Sorcin (SRI) which is a 22kDa calcium-binding protein was originally identified in multidrug-resistant cells. Sorcin, which modulates excitation-contraction coupling in the heart, contributes to calcium homeostasis in the heart sarcoplasmic reticulum.

FHIT enzyme cleaves adenosine 5'' PPP 5'' A to yield AMP and ADP. FHIT gene includees the regular fragile site FRA3B on chromosome 3. Alterations and deletions of the FHIT gene are highly linked to the genesis and establishment of human tumors of the lung, cervix, breast, colon, stomach and pancreas. In normal cells, FHIT functions as a tumor suppressor and physically relates with ubiquitin conjugating enzyme 9.

CBX1 is an enriched heterochromatin which belongs to the heterochromatin protein family. The centromeres related CBX1 identifies and binds histone H3 tails methylated at 'Lys-9', causing epigenetic repression. Collaboration with lamin B receptor (LBR) can impact the relations between the heterochromatin and the inner nuclear membrane. CBX1 has a vital part in the epigenetic control of chromatin structure and gene expression.

PINK1 is a serine/threonine protein kinase which is found in the mitochondria. PINK1 shields cells from stress-induced mitochondrial dysfunction. Mutations results in one form of autosomal recessive early-onset Parkinson disease.

Fractalkine soluble form is chemotactic for t-cells and monocytes, but not for neutrophils. Fractalkine membrane-bound form promotes adhesion of those leukocytes to endothelial cells. Fractalkine regulates leukocyte adhesion and migration processes at the endothelium and binds to CX3CR1. Natural Human Fractalkine is produced as a long protein (373-amino acid) with an extended mucin-like stalk and a chemokine domain on top. The mucin-like stalk permits it to bind to the cell surface. Fractalkine gene is located on human chromosome 16 along with some CC chemokines known as CCL17 and CCL22.

The 26S proteasome is a multicatalytic proteinase complex with a well ordered structure composed of two complexes- a 20S core and a 19S regulator. PSMD11 is a non-ATPase subunit of the 19S regulator. The 20S core is composed of four rings of 28 non-identical subunits; two rings are composed of 7 alpha subunits and two rings are composed of 7 beta subunits. The 19S regulator is composed of a base that contains six ATPase subunits and two non-ATPase subunits, and a lid that contains up to ten non-ATPase subunits. Proteasomes are spread throughout eukaryotic cells at a high concentration and cleave peptides in an ATP/ubiquitin-dependent process in a non-lysosomal pathway. An indispensable function of a modified proteasome, the immunoproteasome, is the processing of class I MHC peptides.

Clusterin also named Apolipoprotein J (APO-J) is a 75-80 kD disulfide-linked heterodimeric protein containing about 30% of N-linked carbohydrate rich in sialic acid but truncated forms targeted to the nucleus have also been identified.
The precursor polypeptide chain is cleaved proteolytically to remove the 22-mer secretory signal peptide and subsequently between residues 227/228 to generate the a and b chains. These are assembled in anti-parallel to give a heterodimeric molecule in which the cysteine-rich centers are linked by five disulfide bridges and are flanked by two predicted coiled-coil a-helices and three predicted amphipathic a-helices.
Across a broad range of species clusterin shows a high degree of sequence homology ranging from 70% to 80%. It is nearly ubiquitously expressed in most mammalian tissues and can be found in plasma, milk, urine, cerebrospinal fluid and semen.
It is able to bind and form complexes with numerous partners such as immunoglobulins, lipids, heparin, bacteria, complement components, paraoxonase, beta amyloid, leptin and others. Clusterin has been ascribed a plethora of functions such as phagocyte recruitment, aggregation induction, complement attack prevention, apoptosis inhibition, membrane remodeling, lipid transport, hormone transport and/or scavenging, matrix metalloproteinase inhibition.
A genuine function of clusterin has not been defined. One tempting hypothesis says that clusterin is an extracellular chaperone protecting cells from stress induced insults caused by degraded and misfolded protein precipitates.
Clusterin is up- or down regulated on the mRNA or protein level in many pathological and clinically relevant situations including cancer, organ regeneration, infection, Alzheimer disease, retinitis pigmentosa, myocardial infarction, renal tubular damage, autoimmunity and others.

43 kDa receptor-associated protein of the synapse (RAPSN), is expressed in the postsynaptic membrane of skeletal muscle. RAPSN is essential for the clustering of nicotinic acetylcholine receptors (nAChR). In addition RAPSN self-associates via at least two of its seven tetra-tricopeptide repeats (TPRs). RAPSN interacts with the large intracellular domain of the nAChR a subunit all the way through the hydrophobic surface of the coiled-coil domain. RAPSN modifies trafficking of AChR within the cell. Overexpression inhibits agrin-induced AChR clustering pathway. RAPSN also plays a role in postsynaptic congenital myasthenic syndromes.

The 14-3-3 family of proteins plays a key regulatory role in signal transduction, checkpoint control, apoptotic and nutrient-sensing pathways. 14-3-3 proteins are highly conserved and ubiquitously expressed. There are at least seven isoforms, ?, ?, ?, ?, ?, ? and ? that have been identified in mammals. The 14-3-3 tau, a subtype of the 14-3-3 family of proteins, was found in T Cells, brain and testes. This 14-3-3 tau is upregulated in patients with amyotrophic lateral sclerosis.

Lysyl Oxidase also known as LOX is an extracellular copper enzyme which initiates the crosslinking of collagens and elastin. LOX catalyzes oxidative deamination of the epsilon-amino group in certain lysine and hydroxylysine residues of collagens and lysine residues of elastin. Adding up to crosslinking extracellular matrix proteins, LOX plays a part in tumor suppression. Moreover, defects in LOX are the cause of autosomal recessive cutis laxa type I, CL type I. Two transcript variants encoding dissimilar isoforms have been found for LOX.

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.

USE1 Belongs to the USE1 family, this protein is a vesicle transport protein. USE1 is a component of a SNAREcomplex consisting of STX18, USE1L, BNIP1/SEC20L and SEC22B. In addition USE1 interacts directly with STX18. SNARE maybe involved in targeting and fusion of Golgi-derived retrograde transport vesicles with the ER. Diseases associated with USE1 comprise dysentery and hemolytic-uremic syndrome. Among its related super-pathways are Nicotine Pathway (Dopaminergic Neuron) and Pharmacodynamics. GO annotations related to this gene include protein binding.

Tyrosyl-tRNA synthetase (YARS2) is a mitochondrial protein which catalyzes the attachment of tyrosine to tRNA(Tyr) in a two-step reaction: tyrosine is first activated by ATP to form Tyr-AMP and afterward transferred to the acceptor end of tRNA(Tyr). YARS2 gene mutations are linked with myopathy with lactic acidosis and sideroblastic anemia type 2 (MLASA2).

HBsAg is the surface antigenof the Hepatitis-B-Virus (HBV). The capsidof a virus has different surface proteins from the rest of the virus. The antigen is a protein that binds specifically on one of these surface proteins. It is commonly referred to as the Australian Antigen.

Histrelin is a hormone similar to one normally released from the hypothalamus gland in the brain. Histrelin works by decreasing the amount of estrogen and testosterone in the blood. Suppressing estrogen can cause thinning of the bones or slowing of their growth. Histrelin acetate is a potent LHRH agonist which stimulates LH and FSH release and inhibits the actions of sex steroids on the male and female reproductive tracts. After a transient increase, continuous administration results in down regulation of LH and FSH levels followed by a suppression of ovarian and testicular steroid biosynthesis. Histrelin potency in vivo and in vitro is similar to that of the D-Trp6-containing analog. Especially because of its high water solubility and greater lipophilic character, it appears promising for clinical application.

Alpha crystallins are composed of two gene products ; alpha-A and alpha-B, for acidic and basic, respectively. Alpha crystallins can be induced by heat shock and are members of the small heat shock protein (sHSP also known as the HSP20). They act as molecular chaperones and hold them in in large soluble aggregates. These heterogeneous aggregates consist of 30-40 subunits; the alpha-A and alpha-B subunits have a 3:1 ratio, respectively. Two additional function of a-crystallins are an autokinase activity and participation in the intracellular architecture. Alpha-B is expressed widely in many tissues and organs and occurs in many neurological diseases.

XCL1 is a small cytokine belongs to the XC chemokine family that is also known as lymphotactin. XCL1 is found in high levels in spleen, thymus, intestine and peripheral blood leukocytes, and at lower levels in lung, prostate gland and ovary. Cellular sources for XCL1 include activated thymic and peripheral blood CD8+ T cells. This chemokine attracts T cells. In humans, XCL1 is closely related to XCL2, whose gene is found at the same locus on chromosome 1. XCL1 induces it chemotactic function by binding to a chemokine receptor called XCR1.

NPPC is proteolytically managed to create a secreted hormone of the natriuretic peptide family. NPPC is vasoactive and natriuretic and controls the evolution and differentiation of cartilaginous growth plate chondrocytes.

Myostatin (GDF-8) is expressed uniquely in human skeletal muscle as a 12 kDa mature glycoprotein consisting of 113 amino acid residues and secreted into plasma. Myostatin is a member of the transforming growth factor ? superfamily of secreted growth and differentiation factors that is essential for proper regulation of skeletal muscle mass. Studies have shown that myostatin could play an important role in cardiac development and physiology.

Transferrin is the iron-transport protein of vertebrate serum and donates iron to cells through interaction with a specific membrane receptor, CD71. Transferrin appears to be indispensable for most cells growing in tissue culture.
It is referred to frequently as a growth factor because, in analogy to other growth factor-receptor interactions, proliferating cells express high numbers of transferrin receptors, and the binding of transferrin to their receptors is needed for cells to initiate and maintain their DNA synthesis. Apart from its role as an iron transport protein transferrin acts as a cytokine and has functions that may not be related to its iron-carrying capacity.
Human Transferrin is a crucial component for the cultivation of mammalian cells in-vitro. Human Transferrin is Critical for long-term cells growth in-vitro. Human Transferrin is used as detoxificant in media by binding contaminating metal ions. Human Transferrin is often used as a nutrient in fermentation media for recombinant protein and biopharmaceutical production. Additional common uses of Human Transferrin areMolecular weight, Affinity purification of anti-human transferrin antibodies and also as receptor mediated transfection of molecules such as DNA, into cells.