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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.

Human chorionic gonadotropin (hCG) is a peptide hormone produced in pregnancy, that is made by the embryosoon after conception and later by the syncytiotrophoblast(part of the placenta). Its role is to prevent the disintegration of the corpus luteumof the ovaryand thereby maintain progesterone production that is critical for a pregnancy in humans. hCG may have additional functions, for instance it is thought that it affects the immune tolerance of the pregnancy. Early pregnancy testing generally is based on the detection or measurement of hCG.

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.

Uromodulin is the most abundant protein in normal urine. Its secretion in urine follows proteolytic cleavage of the ectodomain of its glycosyl phosphatidylinosital-anchored counterpart that is situated on the luminal cell surface of the loop of Henle. Uromodulin plays a role as a constitutive inhibitor of calcium crystallization in renal fluids. Secretion of uromodulin in urine provides protection against urinary tract infections caused by uropathogenic bacteria. Defects in Uromodulin expression are associated with the autosomal dominant renal disorders medullary cystic kidney disease-2 (MCKD2) and familial juvenile hyperuricemic nephropathy (FJHN). These disorders are characterized by juvenile onset of hyperuricemia, gout, and progressive renal failure. While several transcript variants may exist for this gene, the full-length natures of only two have been described to date. UMOD is involved in regulating the circulating activity of cytokines as it binds to il-1, il-2 and tnf with high affinity.

Tripartite Motif Containing 28 (TRIM28) which is a member of the tripartite motif family includes 3 zinc-binding domains, a RING, a B-box type 1 and a B-box type 2, and a coiled-coil region. TRIM28 mediates transcriptional control by interaction with the Kruppel-associated box repression domain found in many transcription factors. TRIM28 is restricted to the nucleus and connected with particular chromatin regions.

ICAM-3/CD50, or CD50 or Cluster of Differentiation 50 is a protein, part of the intercellular adhesion molecule superfamily. every ICAM peptides are type I transmembrane glycoproteins, bind to leukocyte adhesion LFA-1 & has 2-9 immunoglobulinlike C2-type domains. ICAM-3/CD50 can be found in every leukocyte and acts as a crucial ligand for LFA-1 in the start of the immune system response. ICAM-3/CD50 acts as an adhesion molecule and is also a potent signaling protein.

Babesiosis is a disease caused by apicomplexan parasites of the Babesia genus. The Babesia microti life cycle involves 2 hosts, which include a rodent, mainly the white-footed mouse (Peromyscus leucopus) and a tick in the Ixodes genus. During a blood meal, a Babesia-infected tick introduces sporozoites into the mouse host. Sporozoites pass into the erythrocytes and undergo asexual reproduction (budding). In the blood, some parasites differentiate into male and female gametes, though these cannot be distinguished by light microscopy. The definitive host is the tick. Once ingested by an proper tick, gametes unite and undergo a sporogonic cycle resulting in sporozoites. Transovarial transmission (aka vertical or hereditary transmission) has been detected for "large" Babesia species but not for the "small" Babesia, such as B. microti. Humans enter the cycle when bitten by the infected ticks. Thus during a blood meal, a Babesia-infected tick introduces sporozoites into the human host. Sporozoites then enter erythrocytes and undergo asexual replication (budding). Multiplication of the blood-stage parasites is responsible for the clinical manifestations of the disease. Humans typically are dead-end hosts. However, human-to-human transmission is well acknowledged to occur via contaminated blood transfusions.

TP53-induced glycolysis and apoptosis regulator (TIGAR or C12ORF5), is a 270 amino acid protein induced by the p53 tumor suppressor pathway that functions to protect against oxidative stress. C12ORF5 specifically functions to block glycolysis, leading the pathway to the pentose phosphate shunt and decreasing the intracellular concentration of reactive oxygen species. Therefore, it is thought that C12ORF5 may act to modulate the apoptotic response to p53, thus allowing cells to survive mild or transient stresses.

TOLLIP is a ubiquitin-binding protein that interacts with several Toll-like receptor (TLR) signaling cascade components. TOLLIP regulates inflammatory signaling and is involved in interleukin-1 receptor trafficking and in the turnover of IL1R-associated kinase.

DsbE is a reducing Dsb protein involved in electron transfer for cytochrome c maturation in the periplasm of Escherichia coli. DsbE is one of 12 proteins required for their assembly in the periplasm. DsbE functions is to decrease disulphide bonds formed among correctly paired cysteine residues in the cytochrome c apoproteins prior to haem attachment by CcmF and CcmH.

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.

Limb Bud And Heart Development, (LBH) belongs to the LBH family.LBH is highly expressed in the heart, and expressed at low levels in placenta, lung, skeletal muscle, kidney and liver. In addition, LBH protein is a transcriptional activator which may act in mitogen-activated protein kinase signaling pathway. Among the diseases associated with LBH are celiac disease, and rheumatoid arthritis.

Ubiquitin-conjugating enzyme E2S (UBE2S) belongs to the ubiquitin-conjugating enzyme family. UBE2S is able to form a thiol ester linkage with ubiquitin in a ubiquitin activating enzyme-dependent manner, a typical property of ubiquitin carrier proteins. UBE2S catalyzes the covalent attachment of ubiquitin to other proteins. UBE2S acts as a crucial factor of the anaphase promoting complex/cyclosome (APC/C), which is a cell cycle-regulated ubiquitin ligase that controls progression through mitosis. UBE2S acts by purposely elongating ''Lys-11''-linked polyubiquitin chains initiated by the E2 enzyme UBE2C/UBCH10 on APC/C substrates, augmenting the degradation of APC/C substrates by the proteasome and promoting mitotic exit. UBE2S also acts by elongating ubiquitin chains initiated by the E2 enzyme UBE2D1/UBCH5 in vitro; it is nevertheless uncertain whether UBE2D1/UBCH5 acts as an E2 enzyme for the APC/C in vivo. UBE2S is also involved in ubiquitination and consequent degradation of VHL, resu

RDBP is a putative RNA binding protein. RDBP protein is one of the five components of the multisubunit NELF complex which collaborates with DSIF to repress RNA polymerase II elongation. Control of transcription elongation needs a complex interaction between positive transcription elongation factor b and negative transcription elongation factors, DSIF and NELF. DSIF and NELF, act as negative transcription elongation factors by increasing the time the polymerase spends at pause sites. RDBP has a functional RNA-binding domain, whose mutations impair transcription repression without affecting known protein-protein interactions.

HSP104 is a molecular chaperone required for stress tolerance and for maintenance of [psi(+)] prions in the budding yeast Saccharomyces cerevisiae. Hsp104 can protect yeast cells against high temperature and high concentration of ethanol but mutation studies have shown this protein is not required for normal growth. Hsp104 was cloned into an E. coli expression vector and was purified to apparent homogeneity by using conventional column chromatography techniques.

Adiponectin is a recently discovered 244 amino acid protein, the product of the apM1 gene, which is physiologically active and specifically and highly expressed in adipose cells (Adipokine). The protein belongs to the soluble defense collagen super family; it has a collagen-like domain structurally homologous with collagen VIII and X and complement factor C1q-like globular domain. APM-1 forms homotrimers, which are the building blocks for higher order complexes found circulating in serum.

Non muscle Myosins are required for cytokinesis at the end of cell division, when a contractile ring near the plasmalemma divides the cytoplasm of the daughter cells. They are involved in cytoplasmic streaming movements in tissues, and especially in activation of motile cells such as fibroblasts and macrophages. Activation of non-muscle myosin-II is achieved by phosphorylation of Ser33 in the motif KKRPQRATSN by a dedicated, Ca +2 Calmodulin regulated light chain kinase (MLCK).

sRAGE is a member of the immunoglobulin superfamily of cell surface molecules. sRAGE is a receptor for various molecules, including the amyloidogenic form of serum amyloid A, amyloid-beta protein, members of the S100/calgranulin superfamily and advanced glycation end products. sRAGE lies within the major histocompatibility complex (MHC) class III region on chromosome 6. Alternative splicing results in two transcript variants encoding different isoforms. sRAGE mediates interactions of nonenzymatic glycosylated proteins which accumulate in vascular tissue during aging & at an increasing rate in diabetes. sRAGE is a receptor for amyloid beta peptide.

Inositol Monophosphatase Domain Containing 1 or IMPAD1 is a protein, part of the inositol monophosphatase group of proteins. The protein is found in Golgi apparatus and enhances phosphoadenosine phosphate hydrolysis to adenosine monophosphate. When Mutation in the IMPAD1 gene occurs leads to GRAPP type chondrodysplasia and therefore joint dislocations. On long arm chromosome 1 a pseudogene can be found.

Secretoglobin Family 1D, Member 1 (SCGB1D1) belongs to the lipophilin subfamily, part of the uteroglobin superfamily, and is an ortholog of prostatein (which is the major secretory glycoprotein of the rat ventral prostate gland). SCGB1D1 binds androgens and other steroids. In addition SCGB1D1 binds chemotherapeutic drugs during the prostate cancer treatment. Steroid hormones regulate the SCGB1D1 transcription. SCGB1D1 is secreted into extracellular space. SCGB1D1 gene product represents one component of a heterodimeric molecule found in human tears whose elution profile is consistent with prostatein (which is a tetrameric molecule comprised of 3 peptide components in heterodimers).

Thyroid Hormone Responsive (THRSP) is a member of the SPOT14 family. THRSP is similar to the gene product of S14, a rat gene whose expression is limited to liver and adipose tissue and is controlled by nutritional and hormonal factors. THRSP is expressed in liver and adipocytes, specifically in lipomatous modules. In addition It is expressed in lipogenic breast cancers, which suggests a role in controlling tumor lipid metabolism.

Age-Related Maculopathy Susceptibility 2 or ARMS2 is a protein that is is being researches for its ability to take part in diseases in old age. Mutations in Age-Related Maculopathy Susceptibility 2 is related to age-caused molecular degeneration.