Search results

Lamin-A is a major component of the nuclear lamina, a dynamic meshwork located just under the nuclear envelope and it is encoded by lamin A/C gene (LMNA).
Lamin-A is synthesized as Prelamin A, a longer precursor that in vivo goes through a serial post-translational modifications that lead to mature Lamin A.
Diverse mutations in the Lamin A/C gene are associated with different diseases that are collectively called laminophaties, including Emery-Dreifuss muscular dystrophy, familiar partial lipodystrophy, limb girdle muscular dystrophy, dilated cardiomyopathy, Charcot-Marie-Tooth disease, and Hutchinson-Gilford progeria syndrome.

Paraoxonase 1 also called Esterase-A is involved in the detoxification of organophosphate insecticides such as parathion. Paraoxonase 1 may also confer protection against coronary artery disease by destroying proinflammatory oxidized lipids present in oxidized low-density lipoproteins (LDLs).

Glucokinase or GLK, is a protein, part of the bacterial glucokinase superfamily. In the bacteria E. coli, glucose can be transported to the inner cell through a system called PTS as glucose 6-phosphate, therefore, GLK is less crucial to the bacteria.

Casein kinase I gene family members take part in the control of cytoplasmic and nuclear processes, including DNA replication and repair. Casein Kinase 1 Delta (CSNK1D) is a member of the casein kinase I (CKI) gene family. CSNK1D is a vital serine/threonine-protein kinase which regulates diverse cellular growth and survival processes including Wnt signaling and circadian rhythms. CSNK1D phosphorylates a great amount of proteins.

B lymphoid kinase (BLK) is a 55kDa tyrosine kinase with SH3, SH2, and catalytic domains which contain consensus sequences of the Src protein tyrosine kinase family. BLK is a nonreceptor tyrosine-kinase belonging to the src family of proto-oncogenes which are typically involved in cell proliferation and differentiation. The BLK protein is expressed specifically in the B cell lineage and has a role in the signal-transduction pathway which is restricted to B lymphoid cells. In addition, BLK stimulates ins. synthesis and secretion in response to glucose and increases the expression of several pancreatic beta-cell transcription factors.

TIE-1 (tyrosine kinase with Ig and EGF homology domains 1) and TIE-2/Tek comprise a receptor tyrosine kinase (RTK) subfamily with unique structural characteristics: two immunoglobulin-like domains flanking three epidermal growth factor (EGF)-like domains and followed by three fibronectin type III-like repeats in the extracellular region and a split tyrosine kinase domain in the cytoplasmic region. These receptors are expressed primarily on endothelial and hematopoietic progenitor cells and play critical roles in angiogenesis, vasculogenesis and hematopoiesis. Human TIE-1 cDNA encodes a 1122 amino acid (aa) residue precursor protein with an 18 residue putative signal peptide, a 726 residue extracellular domain and a 353 residue cytoplasmic domain. Two ligands, angiopoietin-1 (Ang1) and angiopoietin-2 (Ang2), which bind TIE-2 with high-affinity have been identified. Ang2 has been reported to act as an antagonist for Ang1. Mice engineered to overexpress Ang2 or to lack Ang1 or Tie-1 display similar angiogenic defects.

The protein kinase A holoenzyme is a heterotetramer composed of two types of subunits: Catalytic and Regulatory. The Catalyticsubunit contains the enzyme's active site. It also contains a domain that binds ATP and a domain that binds the regulatory subunit. The Regulatory subunit consists oftwo molecules which bind one another in an anti-parallel orientation to form a homodimer; for type I subunits- this binding is covalent via disulfide bonds. This subunit also has has two domains that bind cyclic AMP, a domain that interacts with a catalytic subunit, and an "auto-inhibitory" domain that serves as a substrate or pseudosubstrate for the catalytic subunit. Regulatory subunits may also have biologic activity distinct from their role in modulating catalytic subunit activity. Regulatory subunits exist in two major forms, RI and RII, with each form having two subtypes designated alpha and beta. Each of the four isotypes of the regulatory subunit is encoded by a different gene. In addition, three isotypes of the catalytic subunit have been identified (alpha, beta and gamma). The different isotypes tend to have different distributions within cells and among tissues. Type I enzymes inhabit cytoplasmic, soluble fractions of the cell, whereas type II enzymes tend to associate with cellular membranes.

cAMP-dependent protein kinase inhibitor beta (PKIB) belongs to the cAMP-dependent protein kinase inhibitor family. PKIB may interact with the catalytic subunit of cAMP-dependent protein kinase and function as a competitive inhibitor.

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.

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, β, γ, ε, σ, ζ, τ and η that have been identified in mammals. The 14-3-3 epsilon, a subtype of the 14-3-3 family of proteins, was thought to be brain and neuron-specific. It has been shown to interact with CDC25 phosphatases, RAF1 and IRS1 proteins, suggesting its role in diverse biochemical activities related to signal transduction, such as cell division and regulation of sensitivity. It has also been implicated in the pathogenesis of small cell lung cancer.

OAS1 enzyme is a member of the 2’,5’-oligoadenylate synthetase family. OAS1 is induced by interferons and uses adenosine triphosphate in 2’-specific nucleotidyl transfer reactions to synthesize 2’,5’-oligoadenylates(2-5As). These molecules in turn activate latent RNase L resulting in viral RNA degradation and the inhibition of viral replication.
OAS1 may have a role in mediating resistance to virus infection, control of cell growth, differentiation, and apoptosis. OAS1 binds double-stranded RNA and polymerizes ATP into PPP (A2'P5'A)N oligomers, which activate the latent RNase L that, once activated, cleaves single-stranded RNAs.
OAS1 gene mutations are been linked to host susceptibility to viral infection.
OSA1 gene polymorphisms are linked to the outcome of hepatitis C virus infection. Furthermore, OAS1 gene polymorphisms are linked to the susceptibility to severe acute respiratory syndrome.

Beta-1,3-N-Acetylglucosaminyltransferase 2 (B3GNT2) is a part of the beta-1,3-N-acetylglucosaminyltransferase family which takes part in the synthesis of poly-N-acetyllactosamine. B3GNT2 is a type II transmembrane protein which prefers the substrate of lacto-N-neotetraose. B3GNT2 catalyzes the initiation and elongation of poly-N-acetyllactosamine chains and comprises the main polylactosamine synthase.

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.

Trichomonas vaginalis, an anaerobic, flagellated protozoan parasite, is most dominant protozoan causing sexual transmitted disease. T. vaginalis induced vaginal tract infection occurs as multiple steps involving interactions between host macromolecules and protozoan virulent factor. Adhension protein P65 of T. vaginalis has a vital part in assisting the penetration into vaginal tract surface.

IFN-gamma produced by lymphocytes activated by specific antigens or mitogens.
IFN-gamma, in addition to having antiviral activity, has important immunoregulatory functions, it is a potent activator of macrophages, and has antiproliferative effects on transformed cells and it can potentiate the antiviral and antitumor effects of the type I IFNs.

E3 ubiquitin-protein ligase SIAH1 (SIAH1) belongs to the SIAH (seven in absentia homolog) family. SIAH1 is a tumor suppressor protein, which is expressed in intestinal epithelium and activated during apoptosis. SIAH1 is involved in ubiquitination and proteasome-mediated degradation of specific proteins. SIAH1 is comprised of an N-terminal RING-finger domain (required for proteolysis) and a cystein-rich C-terminal domain (which regulates oligomerization and SIAH binding to target proteins). SIAH1 causes indirect degradation of beta-catenin by way of creation of a complex with Siah-interacting protein (SIP), Skp1 and Ebi.

AURKA (Aurora Kinase A) belongs to the mitotic serine/threonine kinases family. AURKA is a cell cycle-regulated kinase which may be involved in microtubule formation and/or stabilization at the spindle pole during chromosome segregation. AURKA is found at the centrosome in interphase cells and at the spindle poles in mitosis. Since the AURKA expression is cell-cycle regulated, it is low in G1/S, it accumulates during G2/M, and it decreases rapidly after. AURKA is involved in important processes during mitosis and meiosis whose proper function is essential for healthy cell proliferation. In addition, AURKA plays an essential role in tumourigenesis and is overexpressed in various types of cancers. AURKA is strongly expressed in the testis, colon, ovarian, prostate, neuroblastoma, breast and cervical cancer cell lines and weakly in skeletal muscle, thymus and spleen. AURKA interacts with its substrates BORA and ARHGEF2, as well as with TACC1 and CPEB1.
Defects in the AURKA gene cause numerical centrosome aberrations including aneuploidy. AURKA overexpression has been linked to chromosomal instability in colorectal cancer. AURKA expression may have a prognostic significance in ovarian carcinoma.

Kallikrein-10 (KLK10) is one of the 15 kallikrein subfamily members located in a cluster on chromosome 19. Kallikreins are a subgroup of serine proteases having various physiological functions. KLK10 is secreted and has a role in suppression of tumorigenesis in breast and prostate cancers.

The proteasome is a multicatalytic proteinase complex which holds an extremely organized 20S core structure shaped like a ring. The central structure is assembled from 4 rings of 28 non-identical subunits; 2 rings are composed of 7 alpha subunits and 2 rings are composed of 7 beta subunits. There is a high concentration of proteasomes all over the eukaryotic cells and their job is to cleave peptides in an ATP/ubiquitin-dependent procedure in a non-lysosomal pathway. PSMA3 encodes several of the peptidase T1A family which is a 20S core alpha subunit. Two alternative transcripts encoding diverse isoforms were recognized.

LCMT1 is a member of the LCMT family, methyltransferase superfamily. LCMT1 catalyzes the methylation of the carboxyl group of the C-terminal leucine residue (leu309) of the catalytic subunit of protein phosphatase-2A to form alpha-leucine ester residues.

LAMTOR4 is implicated in amino acid sensing and activation of mTORC1, which is a signaling complex promoting cell growth in response to growth factors, energy levels, and amino acids. LAMTOR4 is activated by amino acids via a mechanism which involves the lysosomal V-ATPase, the Ragulator functions as a guanine nucleotide exchange factor activating the small GTPases Rag. Activated Ragulator and Rag GTPases both function as a scaffold recruiting mTORC1 to lysosomes where it is sequentially activated.

Kallikrein-3 (KLK3) belongs to the kallikrein-related peptidase family. Kallikreins are a subgroup of serine proteases having various physiological functions. Numerous kallikreins are involved in carcinogenesis and some may be prospective cancer and other disease biomarkers. Kallikrein-3 is 1 of the 15 kallikrein subfamily members located in a cluster on chromosome 19 and is a protease present in seminal plasma. KLK3 hydrolyzes semenogelin-1 consequently leading to the liquefaction of the seminal coagulum. KLK3 is assumed to act normally in the liquefaction of seminal coagulum, probably by hydrolysis of the high molecular mass seminal vesicle protein. Serum level of the KLK3 protein, called PSA in the clinical setting, is beneficial in the diagnosis and monitoring of prostatic carcinoma.

PI3Ka plays a specific role in apoptosis in human colon cancer cells. Injection of neutralizing antibodies specific to PI3Ka into adenocarcinoma cells induced apoptosis, a response that was reverted by treating cells with caspase inhibitor. It was also shown that PI3Ka mediated phosphorylation of the p85a adapter reduces the lipid kinase activity of the heterodimer and this gives hints for PI3K-dependent signaling events not requiring production of 3’-phosphorylated phosphoinositides.
PI3Ka is a key regulator of the initiation of keratinocyte differentiation. A decrease in PI3Ka activity results in a loss of keratinocyte adhesion to the extracellular membrane and the initiation of early phase differentiation.