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Ketohexokinase catalyzes the phosphorylation of fructose to produce fructose-1-phosphate, resulting in the utilization of ATP and creation of AMP. Ketohexokinase commences initial step in the metabolism of dietary fructose and is a significant regulator of hepatic glucose metabolism. Ketohexokinase is found in liver, renal cortex, and small intestine. Its deficiency causes the benign hereditary metabolic disorder essential fructosuria, leading to fructose being excreted in the urine. Ketohexokinase-dependent metabolism of fructose induces proinflammatory mediators in proximal tubular cells. ketohexokinase plays an unknown physiologic function that remains intact in essential fructosuria. Ketohexokinase expression is reduceed in human clear cell type of renal cell carcinoma.

EFNB1 is a member of the Eph family. The cell-surface proteins Ephrins split into two groups, ephrin-A and ephrin-B, based on their structure and function and perform as ligands for Eph receptors. The transmembrane EFNB1 proteins have conserved cytoplasmic tyrosine residues that are phosphorylated upon interaction with an EphB receptor. In addition, EFNB1 transduces outside-in signals by C-terminal protein interfaces which influence integrin-mediated cell attachment and migration.

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.

Human thyrostimulin ranks among the glycoprotein hormone family. These hormones consist of two subunits, the common alpha- and specific beta-subunits, which associate noncovalently to form a heterodimer. The alpha-subunit combines with four distinct beta-subunits giving rise to four biologically active hormones in human: FSH, LH, TSH, and CG. FSH, LH, and TSH, mainly expressed in the anterior pituitary, are essential for coordinated endocrine regulation in the hypothalamus- pituitary axis and show to activate specific G protein–coupled receptors in the thyroid (TSH receptor) and gonads (LH and FSH receptors), respectively.
The heterodimeric glycoprotein hormones have only been identified in vertebrates and are highly conserved in organisms from primitive rayfin fish (Chondrostei) to human in both primary sequences and functional characteristics.
Corticotroph-derived glycoprotein hormone (CGH), also referred to as thyrostimulin, is a noncovalent heterodimer of glycoprotein hormone alpha 2 (GPHA2) and glycoprotein hormone beta 5 (GPHB5).
Recombinant A2/B5 heterodimeric glycoproteins activates human TSH receptors, but not LH and FSH receptors, and shows high affinity to TSH receptors in a radioligand receptor assay. The heterodimer also stimulates cAMP production and thymidine incorporation by cultured thyroid cells and increases serum thyroxine levels in TSH-suppressed rats in vivo. This new heterodimeric glycoprotein hormone was named as thyrostimulin based on its thyroid-stimulating activity. The expression of thyrostimulin in the anterior pituitary known to express TSH receptors suggested a paracrine mechanism.

CPLX1 is part of the SNARE family complex binding proteins that are catalysts or inhibitors of vesicle exocytosis. CPLX1 shows reduced Ca2+-triggered fast neurotransmitter release at hippocampal glutamatergic synapses, indicating that CPLX1 is a positive regulator of transmitter release. In contrast, CPLX1 inhibits SNARE-mediated liposome and cell fusions in vitro, that result in hypothesis thus acts as a fusion clamp of synaptic exocytosis. CPLX1 regulates a late step in synaptic vesicle exocytosis.

STAR facilitates the fast increase in pregnenolone synthesis stimulated by tropic hormones. STAR increases pregnenolone synthesis more than four-fold and a major STAR transcription of 1.6 kb is observed in ovary and testis. Throughout the growth and differentiation period of the ovary follicle, the immunoreactivity is likely to move from the granulosa cells of early antral follicles to the theca cell layers in the adult.

HB-EGF is an EGF related growth factor which signals via the EGF receptor, and stimulates the proliferation of SMC (smooth muscle cells), fibroblasts, epithelial cells and keratinocytes. HB-EGF is expressed in various cell types and tissues, including vascular endothelial cells and SMC, macrophages, skeletal muscle, keratinocytes and particular tumor cells. HB-EGF’s ability to explicitly bind HPR sulfate proteoglycans is dissimilar from other EGF-like molecules, and might be related to the enhanced mitogenic activity, relative to EGF, that HB-EGF exerts on smooth muscle cells.

AKR1C4 is a member of the aldo/keto reductase superfamily that has over 40 known enzymes and proteins. AKR1C4 enables the conversion of aldehydes and ketones to their corresponding alcohols by using NADH and/or NADPH as cofactors. AKR1C4 takes part in the bioreduction of chlordecone, a toxic organochlorine pesticide, to chlordecone alcohol in liver.

Inhibins are dimeric peptide hormones produced by female ovarian granulose cells and male Sertoli cells as well as a variety of other tissues. Inhibins have two isoforms, A and B, with the same alpha subunit but different beta subunits. Inhibin A is a dimer of alpha and beta A subunits, inhibin B is a dimer of alpha and beta B subunits.
Inhibins are thought to inhibit the production of follicle-stimulating hormone (FSH) by the pituitary gland. In addition, Inhibins are also thought to play a role in the control of gametogenesis, and embryonic and fetal development.

Myeloid/Lymphoid Leukemia Translocated To 11 (MLLT11) is a part of the Mixed-Lineage Leukemia protein family. MLLT11 which takes part in leukemogenesis and in the progression of severe monocytic leukemia (AML) is located on chromosome 11q23. MLLT11 which is also expressed in embryonic brain cortex is upregulated during neuronal differentiation and is taking part in the evolution of the central nervous system.

Agrin or AGRN is a large protein (proteoglycan) that has a crucial part in the development of neuromuscular junction amid embryogenesis. The protein has an involvement in the collection and aggregation of acetylcholine receptors through synaptogenesis. The agrin gene can be found and expressed in rat embryonic nervous system andmuscle tissue. This Agrin protein is aggregated in the synapses, there it can take part in regeneration & development. The protein binds to receptors on the surface of skeletal muscle.

Alpha 1-microglobulin (A1M) is a lipocalin superfamily member (kernal lipocalins). A1M is a low molecular weight protein component of plasma. A1M is distributed in plasma and extravascular compartments of all organs. Alpha-1 Microglobulin is found in mammals, birds, amphibians and fish. The primary sites of A1M synthesis are the liver and the kidney. Around the opening of the lipocalin pocket three lysyl residues are situated; those residues carry yellow-brown modification derived from the binding and degradation of heme and kynurenin (a tryptophan metabolite). A1-Microglobulin’s reductase and dehydrogenase have broad biological substrate specificity properties due to its’ free cysteine side-chain which is located in a flexible loop. Alpha-1-microglobulin is glycosylated by three separate carbohydrate chains: two complex carbohydrates which are N-linked to asparagines at residues 17 and 96, and the other simple carbohydrate which is O-linked to threonine at position 5. The carbohydrates comprise 22% of the total molecular mass of the protein. The glycosylation varies between species.
A1M exists in two forms- a free form and complexed to other macromolecules: in humans- complexed to immunoglobulin A (IgA), in rat- complexed to alpha-1-inhibitor-3. Free A1M is exceptionally heterogeneous in charge (therefore also known as protein HC), and is found tightly linked to a chromophore. The free Alpha-1-microglobulin is a monomeric protein composed of one 188 residue polypeptide and contains three cysteines, two of which (residues 75 and 173) form a conserved intra-molecular disulphide link. The chromophoric group is covalently bound to the free cysteine residue at position 34. A1M binds retinol as a major ligand, but this is probably distinct from its covalent chromophore.
Half of all human plasma A1M (approximately 0.03mg/ml) forms a 1:1 complex with about 5% of plasma immunoglobulin A. The resulting macromolecular complexes’ molecular weight is 200000, and a plasma concentration of 0.3mg/ml. The complex can exhibit both antibody activity and affect many of the biological actions of free Alpha-1-microglobulin.
Alpha-1-microglobulin was first discovered in pathological human urine.
It was suggested that A1M might be involved in tissue defense against reactive oxygen species, oxidation by heme and kynurenin. Evidence also suggests that A1M functions in the regulation of the immune system. Other functions include inhibition of stimulation of cultured lymphocytes by protein antigens; induction of cell division of lymphocytes, a mitogenic effect that can either be enhanced or inhibited by the action of other plasma components; inhibition of neutrophil granulocyte migration in vitro; and inhibition of chemotaxis.

Sclerostin (SOST) is a secreted glycoprotein with a C-terminal cysteine knot-like (CTCK) domain and sequence similarity to the DAN (differential screening-selected gene aberrative in neuroblastoma) family of bone morphogenetic protein (BMP) antagonists. Sclerostin functions as a negative regulator of bone growth, by inhibiting bone formation. SOST is widely expressed at low levels, with highest levels in the bone, cartilage, kidney, liver, bone marrow and primary osteoblasts differentiated for 21 days. SOST gene defects cause sclerosteosis and bone dysplasia.

Calretinin is an intracellular calcium-binding protein belonging to the troponin C superfamily characterized by a structural motif described as the EF-hand domain. The immunohistochemical detection of calretinin in developing cerebellum is restricted to the later stages indicated by weak staining from week 21 of gestation, in Purkinje and basket cells and in neurons of the dentate nucleus. The intensity of staining increases as the cerebellum matures. In tumors, calretinin has been detected in mesotheliomas and some pulmonary adenocarcinomas.

CD207 (C-type lectin domain family 4 member K) is expressed in Langerhans cells which are immature dendritic cells of the epidermis and mucosa. Moreover, CD207 is expressed in several other dendritic cell types including dermal CD103+ DCs and splenic CD8+ DCs. Langerin is localized in the Birbeck granules, the organelles present in the cytoplasm of Langerhans cells and comprised of superimposed and zippered membranes. CD207 is a C-type lectin with mannose binding specificity, and it has been suggested that mannose binding by the CD207 protein leads to internalization of antigen into Birbeck granules thus providing access to a nonclassical antigen-processing pathway.

Geminin is a 25 kDa nuclear protein, which inhibits DNA replication and is degraded during the mitotic phase of the cell cycle. Geminin controls replication by binding to the licensing factor Cdt1, and is involved in neural differentiation. In addition, Geminin directly interacts with Six3 and Hox homeodomain proteins during embryogenesis and inhibits their functions. Geminin can also promote DNA replication. Geminin has 2 roles in 2 different stages of the cell cycle: Geminin is a negative regulator of DNA replication during the “S phase” of the cell cycle. Inhibition of Geminin during the “S phase” (by RNAi) results in an additional round of replication of portions of the genome. During the “M phase” of the cell cycle (mitosis) Geminin stabilizes the replication factor Cdt1 promoting DNA replication during the next cell cycle. Moreover, inhibition of Geminin during mitosis (by RNAi) causes destabilization of Cdt1 protein and impairment of DNA replication during the next cell cycle. Geminin thus guarantees that only one round of replication occurs during each cell cycle. It was discovered that Geminin is overexpressed in a number of malignancies and cancer cell lines. This maintains the concept that Geminin has also a positive role in DNA replication and cell cycle progression. Geminin accumulates through S, G2 and M phases of the cell cycle but is absent during the G1 phase. During the metaphase/anaphase transition of mitosis Geminin levels decrease.

The human Lymphocyte Antigen 6 Complex Locus G6F (LY6G6F) protein is a type I transmembrane protein belonging to the immunoglobin (Ig) superfamily, which contains cell-surface proteins involved in the immune system and cellular recognition. The LY6G6F protein has a role in the downstream signal transduction pathways involving GRB2 and GRB7.

C-Type Lectin Domain Family 10, Member A (CLEC10A) is a part of the C-type lectin superfamily. CLEC10A is expressed in immature myeloid dendritic cells and alternatively activated macrophages. CLEC10A takes part in regulating adaptive and innate immune responses and also binds in a calcium dependent way to terminal galactose and N-acetylgalactosamine, linked to serine or threonine.

Vesicle-Associated Membrane Protein 7 (VAMP7) is a member of the synaptobrevin family. VAMP7 is a transmembrane protein, which is a member of the soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) family. VAMP7 is involved in the targeting and/or fusion of transport vesicles to their target membrane during transport of proteins from the early endosome to the lysosome. VAMP7 localizes to late endosomes and lysosomes and is involved in the fusion of transport vesicles to their target membranes. VAMP7 is essential for heterotypic fusion of late endosomes with lysosomes and homotypic lysosomal fusion. It is also necessary for calcium regulated lysosomal exocytosis. In addition, VAMP7 is involved in the export of chylomicrons from the endoplasmic reticulum to the cis Golgi. Furthermore, VAMP7 is needed for exocytosis of mediators during eosinophil and neutrophil degranulation, and target cell killing by natural killer cells.

RAET1E is a member of the MHC class I family. MHC class I family contains main histocompatibility complex (MHC) class I-related genes positioned in a cluster on chromosome 6q24.2-q25.3. RAET1E and RAET1G protein are different from other RAET1 proteins since they have type I membrane-spanning sequences at their C termini instead glycosylphosphatidylinositol anchor sequences.RAET1E acts as a ligand for NKG2D receptor, expressed on the surface of numerous types of immune cells, involves in innate adaptive immune reactions.RAET1E delivers signals to NK cells and advances tumor immune surveillance by inducing the growth of anti-tumor cytotoxic lymphocyte.

Vps20-associated 1 homolog (VTA1) is a member of the VTA1 family. The VTA1 protein is involved in the endosomal multivesicular bodies (MVB) pathway. Furthermore, VTA1 is interacts with CHMP1B, CHMP2A, CHMP5, VPS4B, KIAA0174 (IST1) and possibly CHMP3. VTA1 is believed to be a cofactor of VPS4A/B, which catalyzes membrane-associated ESCRT-III assemblies. In addition, VTA1 is involved in the sorting and down-regulation of EGFR and also in HIV-1 budding.

Procollagen C-endopeptidase enhancer 1, also known as PCOLCE binds to the C-terminal propeptide of type I procollagen and enhances procollagen C-proteinase activity. In addition, C-terminal processed part of PCPE (CT-PCPE) has a metalloproteinase inhibitory activity. Among the diseases which are associated with PCOLCE: bone fracture & oculopharyngeal muscular dystrophy.

Prolactin is a neuroendocrine hormone synthesized primarily by the pituitary gland but also a variety of other cell types including the placenta, brain and uterus. Its primary function is to promote and maintain lactation but has also been shown to have a role in breast cancer development, regulation of reproductive function and immunoregulation.