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ATPaseTransporting Beta 1 (ATP1B1) is a part of the family of Na+/K+ and H+/K+ ATPases beta chain proteins, and the subfamily of Na+/K+ -ATPases. Na+/K+ -ATPase is an essential membrane protein accountable for establishing and maintaining the electrochemical gradients of Na and K ions over the plasma membrane. These gradients are vital for osmoregulation, for sodium-coupled transport of a range of organic and inorganic molecules, and for electrical excitability of muscle and nerve. ATP1B1is combined of 2 subunits, a large catalytic subunit (alpha) and a smaller glycoprotein subunit (beta). The beta subunit regulates the number of sodium pumps transported to the plasma membrane through assembly of alpha/beta heterodimers. ATP1B1 is a beta 1 subunit.

Rnase P protein, AKA rnpA, is an important enzyme consisting of the C5 protein (which encoded by rnpA) and the catalytic M1 RNA (encoded by rnpB) subunits. rnpA is ribonucleoprotein that catalyzes the removal of the 50- leader elements of precursor tRNAs and generates the mature 50-end of tRNAs. This step is critical for theformation of functional tRNA molecules in bacteria, archaea and eukarya. More importantly, it has lately been established that RNase P is essential for the endonucleolytic separation of certain polycistronic tRNA transcripts such as valV valW, leuQ leuP leuV and secG leuU. Therefore, it was hypothesized that the essential function of RNase P might be related to the complete absence of a particular tRNAthat was dependent on the enzyme for initial separation from polycistronic transcripts.

FKBP14 enzyme accelerates the folding of proteins during protein synthesis. FKBP14 contains 2 EF-hand domains and one PPIase FKBP-type domain. Truncation of the amino-terminus of FKBP14 significantly decreases peptidyl prolyl cis-trans isomerase activity, therefore implicating that the PPIase FKBP-type domain must be located at the N-terminus.

ANXA1 is part of the family of Ca(2+)-dependent phospholipid binding proteins which have a Mw between 35kDa-40kDa and are situated on the cytosolic face of the plasma membrane. ANXA1 protein has a Mw of 40kDa, with phospholipase A2 inhibitory activity to bind from two to four calcium ions with high affinity. Since phospholipase A2 is necessary for the biosynthesis of the potent mediators of inflammation, prostaglandins and leukotrienes, ANXA1 might have potential anti-inflammatory activity. ANXA1 promotes membrane fusion and iplays a role in exocytosis. The recognition of ANXA1 protein by immunocytochemical leads a simple, highly sensitive and specific assay for diagnosis of hairy cell leukemia.

Guanine Nucleotide Binding Protein Gamma 12, also known as GNG12 belongs to the Guanine nucleotide-binding proteins (G proteins) which are involved as a modulator or transducer in a variety of transmembrane signaling systems. In addition, the beta as well as gamma chains are essential for the GTPase activity, for replacement of GDP by GTP, and also for G protein-effector interaction.

Cytochrome b-c1 complex subunit 2, mitochondrial (UQCRC2) is a member of the peptidase M16 family. UQCRC2 is a component of the ubiquinol-cytochrome c reductase complex (complex III), which is a part of the mitochondrial respiratory chain. UQCRC2 is essential for the compilation of the complex.

EFNA3 belongs to the ephrin (EPH) family. The ephrins and EPH-related receptors include thelargest subfamily of receptor protein-tyrosine kinases which have been implicated in mediating developmental events, especially in the nervous system and in erythropoiesis. Ephrins are divided into the ephrin-A (EFNA) class and the ephrin-B (EFNB) class, based on their structures and sequence relationships. The Ephrins from the EFNA class are anchored to the membrane by aglycosylphosphatidylinositol linkage, while the others from the EFNB class are transmembrane proteins.

EFNA3 belongs to the ephrin (EPH) family. The ephrins and EPH-related receptors include thelargest subfamily of receptor protein-tyrosine kinases which have been implicated in mediating developmental events, especially in the nervous system and in erythropoiesis. Ephrins are divided into the ephrin-A (EFNA) class and the ephrin-B (EFNB) class, based on their structures and sequence relationships. The Ephrins from the EFNA class are anchored to the membrane by aglycosylphosphatidylinositol linkage, while the others from the EFNB class are transmembrane proteins.

TSR2 is part of the TSR2 family. TSR2 is involved in 20S pre-rRNA processing. Among the diseases which are associated with TSR2 are blepharospasm and diamond-blackfan anemia.

Annexin A13 (ANXA13) belongs to the annexin protein family, whose members play a role in cytoskeletal interactions, phospholipase inhibition, regulation of cellular growth, and intracellular signal transduction pathways. ANXA13 is believed to be the original originator of the 12 members of vertebrate annexins. ANXA13 expression is decidedly tissue-specific, being expressed only in intestinal and kidney epithelial cells. This expression is linked with a highly differentiated intracellular transport function.

ADP-ribosylation factor 5 (ARF5) is a small guanine nucleotide-binding protein which enhances the enzymatic activities of cholera toxin. ARF-dependent regulatory mechanisms include the coordination of spectrin interactions with golgi membranes and the connection of actin to the golgi via rho family-dependent G-protein localization and WASP/Arp2/3 complexes. ARF5 is involved in vesicular transport and functioning via phospholipase D activation.

Ephrin-B3 (EFNB3) which belongs to the ephrin gene family is essential in brain development as well as in its maintenance. EFNB3 binds to, and induces the collapse of, commissural axons/growth cones in vitro. EFNB3 loosely binds Eph receptors located on bordering cells, leading to contact-dependent bidirectional signaling into neighboring cells. The EPH and EPH-related receptors comprise the largest subfamily of receptor protein-tyrosine kinases and are implicated in mediating developmental events, mostly in the nervous system.

S100A3 is part of S100 family of proteins containing 2 EF-hand calcium-binding motifs. S100 proteins are localized in the cytoplasm/nucleus of a broad range of cells, and takes part in the regulation of several cellular processes such as cell cycle progression and differentiation. S100A3 has the largest number of cysteines of all S100 proteins. S100A3 has high affinity for Zinc, and is widely expressed in human hair cuticle.

Proteasome subunit alpha type-5 (PSMA5) is a member of the peptidase T1A family. The proteasome is a multicatalytic proteinase complex which is distinguished by its ability to cleave peptides with Arg, Phe, Tyr, Leu, and Glu adjacent to the leaving group at neutral or slightly basic pH. Proteasomes are spread throughout eukaryotic cells at a high concentration and cleave peptides in an ATP/ubiquitin-dependent process in a non-lysosomal pathway. PSMA5 interacts with PLK1. The PSMA5 peptidase has a very wide-ranging specificity for cleavage of peptide bonds.

Myosin light polypeptide 6 (MYL6) is a hexameric ATPase cellular motor protein. MYL6 is composed of 2 heavy chains, 2 nonphosphorylatable alkali light chains, and 2o phosphorylatable regulatory light chains. MYL6 is a myosin alkali light chain which is expressed in smooth muscle and non-muscle tissues. MYL6 partakes in generating the force for cellular movements, thus having an imperative role in overall cellular function.

The proteasome is a multicatalytic proteinase complex with a highly assembled ring-shaped 20S core structure which is composed of 4 rings of 28 non-identical subunits, 2 rings are composed of 7 alpha subunits and 2 rings are composed of 7 beta subunits. Proteasomes are found throughout eukaryotic cells at a high concentration and cleave peptides in an ATP/ubiquitin-dependent process in a non-lysosomal pathway. PSMA7 is part of the peptidase T1A family, that is a 20S core alpha subunit. PSMA7 interacts particularly with the hepatitis B virus X protein, a protein critical to viral replication. PSMA7 is involved in regulating hepatitis virus C internal ribosome entry site activity that is crucial for viral replication. PSMA7 is in charge for regulating the hypoxia-inducible factor-1alpha, a transcription factor important for cellular responses to oxygen tension. PSMA7 is characterized by its ability to cleave peptides with Arg, Phe, Tyr, Leu, and Glu adjacent to the leaving group at neutral or slightly basic pH. PSMA7 interacts specifically with two subdomains of HIF-1alpha and inhibited the transactivation function of HIF-1alpha under both normoxic and hypoxia-mimicking conditions.

The proteasome is a multicatalytic proteinase complex with an extremely organized ring-shaped 20S core structure. The core structure consists of 4 rings of 28 non-identical subunits; 2 rings consist of 7 alpha subunits and 2 rings consist of 7 beta subunits. Proteasomes are spread all over the eukaryotic cells in large quantities and cleave peptides in an ATP/ubiquitin-dependent procedure in a non-lysosomal pathway. A vital role of a modified proteasome, the immunoproteasome, is the handling of class I MHC peptides.

SEMA3C, also known as Semaphorin 3C, is a member of the semaphorin family 3 that are grouped into 8 major classes based on phylogenetic tree analyses and structure. Class 3 have an important function after traumatic central nervous system injuries. SEMA3C regulates neuronal and non-neuronal cells associated with the traumatic injury due to their presence in the scar tissue. SEMA3C is expressed in all somatic motor neurons, in cardiac neural crest cells during development and in lung buds. The SEMA3C functions are mediated through binding to the Plexin-D1 and Neuropilin 1 or Neuropilin 2 coreceptor complex. SEMA3C activates integrins in certain cells, so besides its repulsive activities, it also acts as a chemoattractant.

Protein Tyrosine Phosphatase Type IVA Member 3 (PTP4A3) is a member of a small class of prenylated protein tyrosine phosphatases (PTPs) which remove phosphate modifications from tyrosine residues on proteins. PTP4A3 enhances cell proliferation, cell motility and invasive activity. PTP4A3 functions as a protein tyrosine phosphatase which stimulates progression from G1 into S phase during mitosis. PTP4A3 is mostly expressed in cardiomyocytes and skeletal muscle; it is also found in the pancreas.
PTP4A3 is always overexpressed in colon cancer metastasis. PTP4A3 is notably overexpressed in liver metastasis of colorectal cancer. High levels of PTP4A3 expression are linked to tumorigenesis and metastasis; therefore it is overexpressed in metastatic colorectal, ovarian, liver and skin cancers. PTP4A3 may be involved in the progression of cardiac hypertrophy by inhibiting intracellular calcium mobilization in response to angiotensin II. PTP4A3 is inhibited by sodium orthovanadate and peroxovanadium compounds.

Human Factor IX also called Christmas-Factor is a glycoprotein, which is synthesized in the liver and belongs to the serine proteases system and is part of the S1 peptidase family.
Lack of Factor-IX causes Hemophilia-B meaning Christmas Disease. Factor-IX has a N-terminus region which contains 12xGla residues which asist the calcium dpendant binding of Factor-IX to the phospholipid surface. Factor-IX is activated by either factor XIa or the factor VIIa/tissue factor/phospholipid complex. Cleavage yields the intermediate IXa, which is subsequently converted to the fully active form IXab.
Factor-IX binds initially to exosites on the factor XIa heavy chain, followed by interaction at the active site with subsequent bond cleavage. Coagulation factor IX is activated by interaction with the erythrocyte membrane, causing intrinsic coagulation. Chaperones & lectins act simultaniously to guarantee the proper folding of Factor-IX and the retention of mutant molecules. Human Factor IX, activated by either the Contact or Tissue Factor Pathway, is responsible for the activation of Factor X to Xa.

Cadherin-5 (CDH5) belongs to the atypical/type 2 subgroup of Cadherin homophilic adhesion proteins. Cadherin-5 is a calcium-dependent cell-cell adhesion molecule, which is comprised of 5 extracellular cadherin repeats, a transmembrane region and a highly conserved cytoplasmic tail. Cadherin-5 protein plays a role in the formation, maturation and remodeling of the vascular wall. CDH5 is generally considered to be specific for vascular endothelia in which it is either the sole or the predominant cadherin, often co-existing with N-cadherin. Moreover, the CDH5 protein regulates or is regulated by VEGF R2, type 1 and type 2 TGF-beta receptors, and other endothelial junction proteins such as JAM-C, Claudin-5, and N-Cadherin. CDH5 also connects with alpha-catenin forming a link to the cytoskeleton. CDH5 functions jointly with KRIT1 to create and maintain correct endothelial cell polarity and vascular lumen. Furthermore, Cadherin-5 is essential for activation of PRKCZ and for the localization of phosphorylated PRKCZ, PARD3, TIAM1 and RAP1B to the cell junction. The CDH5 gene is located in a gene cluster in a region on the long arm of chromosome 16 which is involved in loss of heterozygosity events in breast and prostate cancer.

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.

POU2AF1 is a lymphocyte specific transcription coactivator protein. POU2AF1 cooperates only with the Oct1/2 proteins using sub domains in the POU domain of the Oct1/2 proteins, increasing their transcriptional efficiency. Even though POU2AF1 have no basic ability to bind DNA, it links firmly with the octomer motif in the presence of Oct1 and Oct2. POU2AF1 is expressed at maximum levels in spleen and peripheral blood leukocytes.

SNTA1 is a member of the syntrophin gene family. SNTA1 is a peripheral membrane protein found linked with dystrophin and dystrophin-related proteins. Dystrophin is a large, rod-like cytoskeletal protein located at the inner surface of muscle fibers. Dystrophin is absent in Duchenne Muscular Dystrophy patients, however it is present in reduced amounts in Becker Muscular Dystrophy patients. Syntrophins are cytoplasmic peripheral membrane scaffold proteins and components of the dystrophin-associated protein complex. The N-terminal PDZ domain of SNTA1 interacts with the C-terminus of the pore-forming alpha subunit (SCN5A) of the cardiac sodium channel Nav1.5. In addition, SNTA1 associates cardiac sodium channels with the nitric oxide synthase-PMCA4b (plasma membrane Ca-ATPase subtype 4b) complex in cardiomyocytes. The SNTA1 gene is a predisposition locus for Long-QT syndrome (LQT) - an inherited disorder associated with sudden cardiac death from arrhythmia - and sudden infant death syndrome (SIDS). SNTA1 also associates with dystrophin and dystrophin-related proteins at the neuromuscular junction and modifies intracellular calcium ion levels in muscle tissue.