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IGFBP6 plays a role in lipoprotein assembly and dietary cholesterol absorption. in addition to its acyltransferase activity, it may act as a ligase. may provide cholesteryl esters for lipoprotein secretion from hepatocytes and intestinal mucosa.

MBP is a major component of the myelin sheath of oligodendrocytes and Schwann cells in the nervous system, although, MBP-related transcripts are also present in the bone marrow and the immune system. These mRNAs emerge from the long MBP gene which holds three additional exons located upstream of the classic MBP exons. The Golli mRNAs contain three exons unique to Golli-MBP, spliced in-frame to one or more MBP exons. The second family of transcripts contains only MBP exons and produces the well characterized myelin basic proteins. MBP transcription unit is an essential part of the Golli transcription unit and the arrangement is important for the function and/or regulation of these genes.

Lactate dehydrogenase (LDH) is an enzyme(EC1.1.1.27) present in a wide variety of organisms, including plants and animals.
A tetrameric enzyme that catalyses the interconversion of pyruvateand lactate with concomitant interconversion of NADH and NAD+. At high concentrations of pyruvate, the enzyme exhibits feedback inhibition and the rate of conversion of pyruvate to lactate is decreased. In vertebrates, genes for three different subunits (LDH-A, LDH-B and LDH-C) exist.

LDL is a low-density lipoprotein that transports cholesterol and triglycerides from the liver to peripheral tissues. LDL (like all lipoproteins) facilitates the movement of fats and cholesterol within the water based solution of the blood stream. Each natural LDL particle contains a single Apo B-100 molecule (apolipoprotein B-100 is a protein with 4536 amino acid residues) that circulates the fatty acids and keeps them soluble in the aqueous environment. Additionally, the LDL core is highly-hydrophobic, consisting of linoleate (a polyunsaturated fatty acid) and about 1500 esterified cholesterol molecules. This core is enclosed by a shell of phospholipids and unesterified cholesterol in addition to a single copy of B-100 large protein (514 kD). Even though the LDL particles are approximately 22 nm in diameter and have a mass of about 3 million Daltons, they have a mass and size distribution since the LDL particles contain a varying number of fatty acids. LDL receptors are synthesized and placed in the plasma membrane when a cell requires cholesterol. The LDL receptors scatter freely until they link to clathrin-coated pits. LDL particles in the blood stream attach to these extracellular LDL receptors. The clathrin-coated pits at that time form vesicles that are endocytosed into the cell. Once the clathrin coat is dropped, the vesicles transport the LDL and their receptors to early endosomes, onto late endosomes to lysosomes. At this point the cholesterol esters in the LDL are hydrolysed. The LDL receptors are recovered back to the plasma membrane. Since LDLs convey cholesterol to the arteries and can be retained there by arterial proteoglycans initializing the formation of plaques, increased levels are linked to atherosclerosis, and thus heart attack, stroke, and peripheral vascular disease. And so, cholesterol within LDL lipoproteins is habitually called "bad" cholesterol. This is a misconception since the cholesterol transported on LDL is the same as the one transported on other lipoprotein particles, it is in itself not "bad", rather it is how and where the cholesterol is being transported, and in what amounts ultimately, which causes adverse effects. HDL / LDL ratio can give an indication of risk for arteriosclerosis.

Leptin is a protein hormone. It is mainly produced in adipose cells that regulate energy homeostasis by restraining hunger. Leptin ties to nuclear receptors in the hypothalamus (arcuate nucleus). Similar to insulin resistance in type II diabetes, in obesity there is a decrease in the sensitivity towards leptin, ending in a failure to identify satiety, even in high levels of energy stores or leptin itself. Full-length cDNA encoding 2 leptin sequences (tLepA and tLepB) and 1 leptin receptor sequence (tLepR) exists in tilapia (Oreochromis niloticus). The full-length cDNA of tLepR is 3423 bp, encoding a protein of 1140 amino acid which contained all functionally important domains conserved among vertebrate leptin receptors. The cDNAs of tLepA and tLepB are 486 bp and 459 bp in length, encoding proteins of 161 aa and 152 aa, respectively. The three-dimensional structures of tLepA and tLepB demonstrates strong conservation of tertiary structure with that of human leptin comprised of 4 helixes.

C4BP has a flower shaped structure with each alpha chain radiating out from a central core. The arms are linked by disulfide bonds in the centre and the ends of each arm bind C4b. C4BP acts as a cofactor allowing factor I to split and permanently inactivate C4b. C4b binding protein modulates complement activation of the classical and lectin pathways. C4BP binds to C4b and accelerates the dissociation of C2a from the C3/C5 convertase C4b,C2a. This inactivates the central enzyme of both pathways. Studies have shown that on surfaces densely coated with C4b, C4BP can bind up to four C4b molecules simultaneously.

Natriuretic Peptide Precursor B acts as a cardiac hormone with a variety of biological actions including natriuresis, diuresis, vasorelaxation, and inhibition of renin and aldosterone secretion. It is thought to play a key role in cardiovascular homeostasis. Helps restore the body's salt and water balance. Improves heart function.

MRPL28 is found in a variety of normal tissues such as spleen, testis, thymus, liver, kidney, brain, adrenal, lung and retinal tissue. 39S ribosomal protein L28, mitochondrial (MRPL28), is a part of the ribosomal protein L28P family. Mammalian mitochondrial ribosomal proteins encoded by nuclear genes and helps in protein synthesis within the mitochondrion. Mitochondrial ribosomes (mitoribosomes) consist of a small 28S subunit and a large 39S subunit. MRPL28 is an important therapeutic reagent for HLA-A24 (A24) patients since this antigen is distinguished by tumor-infiltrating lymphocyte (TIL) 1290, which targets the A24 serotype.

Growth hormone receptor, also known as GHR is part of the cytokine receptor family. GHR binds 2 receptor molecules and in this manner induces signal transduction through receptor dimerization. Furthermore, at high concentrations, growth hormone performs as an antagonist since there is a large difference in affinities at the respective binding sites. The antagonist action can be enhanced further by reducing binding in the low affinity binding site.

Phospholysine phosphohistidine inorganic pyrophosphate phosphatase (LHPP) belongs to the HAD-like hydrolase superfamily. LHPP is an exceptional enzyme which hydrolyzes not only oxygen-phosphorus bonds in inorganic pyrophosphate but also nitrogen-phosphorus bonds in phospholysine, phosphohistidine and imidodiphosphate in vitro. LHPP is expressed in the liver, kidney and moderately in the brain.

Leukemia Inhibitory Factor also called LIF is a lymphoid factor that promotes long-term maintenance of embryonic stem cells by suppressing spontaneous differentiation. Leukemia Inhibitory Factor has several functions such as cholinergic neuron differentiation, control of stem cell pluripotency, bone & fat metabolism, mitogenesis of factor dependent cell lines & promotion of megakaryocyte production in vivo. Human and mouse LIF exhibit a 78% identity in its amino acid sequence.

Prosaposin (PSAP) is a precursor of 4 lysosomal saposin proteins (saposin A, B, C and D). Saposins are heat-stable glycoproteins which facilitate the catabolism of glycosphingolipids with short oligosaccharide groups. PSAP stimulates neurite outgrowth and increases choline acetyltransferase activity. Prosaposin exists both as a secretory protein and as an integral membrane protein and has neurotrophic activities. The secreted prosaposin is assumed to have additional functions in human milk, cerebrospinal fluid and seminal plasma. PSAP gene mutations are linked with Gaucher disease, Tay-Sachs disease, and metachromatic leukodystrophy.

A 16-kDa peptide hormone secreted from white adipocytes and implicated in the regulation of food intake and energy balance. Leptin provides the key afferent signal from fat cells in the feedback system that controls body fat stores.

IGFBP1 is a member of the insulin-like growth factor binding protein (IGFBP) family and encodes a protein with an IGFBP domain and a thyroglobulin type-I domain. The protein binds both insulin-like growth factors (IGFs) I and II and circulates in the plasma. Binding of this protein prolongs the half-life of the IGFs and alters their interaction with cell surface receptors. Alternate transcriptional splice variants, encoding different isoforms, have been characterized.

PEBP1 (Phosphatidylethanolamine binding protein 1) belongs to the phosphatidylethanolamine-binding protein family and a serine protease inhibitor that inhibits thrombin, neuropsin. PEBP1 plays a key modulatory part in several protein kinase signaling cascades. PKC phosphorylates PEBP1, resulting in the release of Raf-1 and activation of MEK and ERK. PEBP1 is expressed in many tissues and implicated in the regulation of such physiological processes as membrane biosynthesis, spermatogenesis, neural development, and metastasis suppression.
PEBP1 binds ATP, opioids and phosphatidylethanolamine, however it has lower affinity for phosphatidylinositol and phosphatidylcholine. PEBP1 may also be involved in the function of the presynaptic cholinergic neurons of the CNS. PEBP1 increases the production of choline acetyltransferase although not acetylcholinesterase. Furtheremore, PEBP1 functions in potentially sequestering toxic compounds, including locostatin which may have harmful effects on cells.
Loss of PEBP1 expression may have a significant role as prognostic marker in Gastrointestinal stromal tumors. In addition, PEBP1 is found differentially expressed in the Wernicke's Area from schizophrenia patients. PEBP1 is also, an invasion suppressor protein in nasopharyngeal carcinoma.

Leucine Aminopeptidase 3 also known as LAP3 is a member of the peptidase M17 family. LAP3 is implicated in the processing as well as regular turnover of intracellular proteins. LAP3 catalyzes the removal of unsubstituted N-terminal amino acids from different peptides. LAP3 is responsible of releasing an N-terminal amino acid, Xaa-|-Yaa-, in which Xaa is preferably Leu, but could be other amino acids including Pro although not Arg or Lys, and Yaa may be Pro. Amino acid amides and methyl esters are as well readily hydrolyzed; however rates on arylamides are exceedingly low.

Lipocalin-1 (LCN1) belongs to the lipocalin family of small secretory proteins. Lipocalins are extracellular transport proteins, which bind to various hydrophobic ligands. LCN1 protein is the principal lipid binding protein in tears and is overproduced in response to numerous stimuli including infection and stress. LCN1 is a marker for chromosome aneuploidy as well as an autoantigen in Sjogren's syndrome.

LDHB is part of the lactate dehydrogenase family. LDHB is an oxidoreductase which catalyses the interconversion of pyruvate and lactate with concomitant interconversion of NADH and NAD+. LDHB catalyzes the oxidation of hydroxybutyrate, and frequently called Hydroxybutyrate Dehydrogenase (HBD). The LDH family consists of three members, LDH-A, LDH-B and LDH-C. LDHs function as powerful markers for germ cell tumors.

LDLRAP1 is a cytosolic protein that holds a phosphotyrosine binding (PTD) domain and performing as a cytosolic adaptor it couples LDLR to endocytic machinery. Mutations in LDLRAP1 are the reason for autosomal recessive hypercholesterolemia (ARH) which is a condition triggered by defective internalization of LDL receptors (LDLR) in the liver.

Lxn also known as Latexin is a member of the protease inhibitor I47 (latexin) family. Lxn's function is hardly reversible, non-competitive, as well as potent inhibitor of CPA1, CPA2 and CPA4. Furthermore, Lxn plays a role in inflammation. Among the diseases associated with LXN are endocervicitis and listeriosis.

Heterogeneous Nuclear Ribonucleoprotein A/B (HNRNPAB) is a member of the subfamily of ubiquitously expressed heterogeneous nuclearribonucleoproteins (hnRNPs). The hnRNPs are produced by RNA polymerase II and are components of theheterogeneous nuclear RNA (hnRNA) complexes. They are linked with pre-mRNAs in the nucleus and seem to influence pre-mRNA processing and further aspects of mRNA metabolism and transport. Whereas all of the hnRNPsare present in the nucleus, some seem to shuttle between the nucleus and the cytoplasm. The hnRNP proteins have distinct nucleic acid binding properties. HNRNPAB, which binds to one of the components of the multiproteineditosome complex, has two repeats of quasi-RRM (RNA recognition motif) domains that bind to RNAs. Among the diseases associated with HNRNPAB are wells syndrome, and cystic fibrosis.

Prohibitin (PHB) is an evolutionarily conserved gene that is ubiquitously expressed and which Mutations have been linked to sporadic breast cancer. PHB is thought to be a negative regulator of cell proliferation and may be a tumor suppressor. Prohibitin is expressed as two transcripts with changeable lengths of 3' untranslated region. The longer transcript is present at higher levels in proliferating tissues and cells, proposing that this longer 3' untranslated region functions as a trans-acting regulatory RNA.