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The heat-shock response is elicited by exposure of cells to thermal and chemical stress and through the activation of HSFs (heat shock factors) results in the elevated expression of heat-shock induced genes. Heat shock factor binding protein-1 (HSBP1), is a 76-amino-acid protein that binds to heat shock factor 1(HSF1), which is a transcription factor involved in the HS response. During HS response, HSF1 undergoes conformational transition from an inert non-DNA-binding monomer to active functional trimers. HSBP1 is nuclear-localized and interacts with the active trimeric state of HSF1 to negatively regulate HSF1 DNA-binding activity. Overexpression of HSBP1 in mammalian cells represses the transactivation activity of HSF1. When overexpressed in C.elegans HSBP1 has severe effects on survival of the animals after thermal and chemical stress consistent with a role of HSBP1 as a negative regulator of heat shock response.

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.

Bcl-2–associated X protein (Bax) belongs to the Bcl-2 protein family.
Bax is a pro-apoptotic Bcl-2 protein containing BH1, BH2 and BH3 domains.
Bax accelerates programmed cell death by binding to, and antagonizing the apoptosis repressor bcl2 or its adenovirus homolog e1b 19k protein. Bax induces the release of cytochrome c, activation of casp3, and thereby apoptosis. Bax is expressed in a wide variety of tissues, with highest levels in the testis and ovary.
Tumor suppressor protein p53 upregulates the expression of BAX. Bax has been shown to be involved in p53-mediated apoptosis.

PIM1, which is a part of the Ser/Thr protein kinase family and PIM subfamily, is expressed primarily in B-lymphoid and myeloid cell lines, and is overexpressed in hematopoietic malignancies and in prostate cancer. PIM1 functions as Proto-oncogene with serine/threonine kinase activity involved in cell survival and cell proliferation, consequently providing a selective advantage in tumorigenesis. Both human and orthologous mouse genes have been reported to encode two isoforms resulting from the use of alternative in-frame translation initiation codons, the upstream non-AUG (CUG) and downstream AUG codons.

Mitochondrial Ribosomal Protein L48, also known as MRPL48, is a mammalian mitochondrial ribosomal protein which assists in protein synthesis within the mitochondrion. Mitochondrial ribosomes, mitoribosomes, consist of a small 28S subunit and a large 39S subunit. They include an estimated 75% protein to rRNA composition while comparing to prokaryotic ribosomes, where this ratio is reversed.An additional dissimilarity between mammalian mitoribosomes & prokaryotic ribosomes is that the latter contain a 5S rRNA. Between different species, the proteins containing the mitoribosome differ very much in sequence, as well as in biochemical properties from time to time, which prevents easy recognition through sequence homology. MRPL48 encodes a 39S subunit protein. A pseudogene corresponding to MRPL48 is found on chromosome 6p.

Sprouty Homolog 4 (SPRY4) is an inhibitor of the receptor-transduced mitogen-activated protein kinase (MAPK) signaling pathway. SPRY4 is positioned upstream of RAS activation. SPRY4 protein functions include suppressing the EGFR-transduced MAPK signaling pathway as well as impairing the formation of GTP-Ras.

Ribosomal protein S2, (RPS2) is a member of the S5P familyof ribosomal proteins. Ribosomes, the organelles which catalyze protein synthesis, consist of a small 40S subunit and a large 60S subunit. Jointly these subunits are composed of 4 RNA species and approximately 80 structurally differentproteins. RPS2 is a ribosomal protein which is a component of the 40S subunit. RPS2located in the cytoplasm. RPS2 shares sequence similarity with mouse LLRep3. RPS2 has been associated with diamond-blackfan anemia, and herpes simplex.

Native human C3 is a naturally glycosylated polypeptide containing two disulfide-linked chains. C3 is central to the activation of all 3 pathways of complement activation. Initiation of each pathway generates proteolytic enzyme complexes which binds the target surface. These enzymes cleave a peptide bond in C3 releasing the anaphylatoxin C3a and activating C3b. Most of the C3 activated during complement activation never attaches to the surface due to its thioester reaction with water forming fluid phase C3b which is rapidly inactivated by factors H and I forming iC3b. Surface-bound C3b is necessary in all 3 pathways for efficient activation of C5 and formation of C5b-9 complexes that lyse the target cell membrane.

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.

Ataxin 3 is otherwise known as Machado-Joseph disease protein 1. Machado–Joseph disease is a hereditary autosomal dominant neurodegenerative disorder. ATXN3 contains trinucleotide CAG repeats in the coding region, and the expansion of these repeats from the normal 13-36 to 68-79 causes the Machado-Joseph disease. ATXN3 is a poly-ubiquitin-binding protein whose cellular turnover is regulated by its catalytic activity.
In addition, ATXN3 is a proteasome-associated factor which mediates the degradation of ubiquitinated proteins. ATXN3 folds reversibly using a single intermediate; partial destabilization of ATXN3 by chemical denaturation causes the formation of fibrillar aggregates by the non-pathological variant.
Ataxin-3 interacts with the major histone acetyltransferases cAMP-response-element binding protein (CREB)-binding protein, p300, and p300/CREB-binding protein-associated factor and hinders transcription by these coactivators.

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.

Kelch Domain Containing 8B, also known as KLHDC8B shapes a distinct beta-propeller protein structure of kelch domains which allow for protein-protein interactions. In addition,mutations in KLHDC8B have been connected with Hodgkin lymphoma.

Mammalian mitochondrial ribosomal proteins are encoded by nuclear genes and assist in protein synthesis within the mitochondrion. Mitochondrial ribosomes (mitoribosomes) consist of a small 28S subunit and a large 39S subunit (MRPL13 is a 39S subunit protein) and have an estimated 75% protein to rRNA composition compared to prokaryotic ribosomes, where this ratio is reversed. An additional difference between mammalian mitoribosomes and prokaryotic ribosomes is that the second contain a 5S rRNA. Among various species, the proteins comprising the mitoribosome differ greatly in sequence, and sometimes in biochemical properties, which prevents easy recognition by sequence homology.

Family with Sequence Similarity 3, Member D (FAM3D) is a member of the FAM3 family. The FAM3D gene is linked to narcolepsy and diabetes mellitus in pancreatic adenocarcinoma, however FAM3D function of remains vague. FAM3D is amply expressed in the placenta and weakly expressed in the small intestine.

PET117 is nuclear gene essential for the assembly of active cytochrome c oxidase in S. cerevisiae. Nevertheless the gene products are not subunits of the final assembled cytochrome c oxidase complex. PET117 is found in chromosome V proximate the HIS1 gene.

NCS1 is part of the neuronal calcium sensor gene family, which encode calcium-binding proteins expressed primarily in neurons. NCS1 regulates G protein-coupled receptor phosphorylation in a calcium-dependent manner and can substitute for calmodulin. NCS1 is related with secretory granules and modulates synaptic transmission and synaptic plasticity. NCS1 regulates GRK1 and substitutes for calmodulin. NCS1 stimulates PI4KB kinase activity and participates in long-term synaptic plasticity through its interaction with PICK1. NCS1 takes part in neuron differentiation through inhibition of the activity of N-type voltage-gated calcium channel.

RAD1 is part of a heterotrimeric cell cycle checkpoint complex, recognized as the 9-1-1 complex, that is activated to stop cell cycle progression in reaction to DNA damage or incomplete DNA replication. RAD1 complex withholds the Rad9 and Hus1 proteins and takes part in cellular responses to DNA damage, by associating with Rad17 and several components of the PCNA-loading heteropentamer, replication factor C. RAD1 takes part in DNA repair and recruited to DNA lesion upon damage by the RAD17-replication factor C (RFC) clamp loader complex. RAD1 takes part as a sliding clamp platform on DNA for several proteins that play a role in long-patch base excision repair (LP-BER). RAD1 complex stimulates DNA polymerase beta (POLB) activity by raising its affinity for the 3''-OH end of the primer-template and stabilizes POLB to those sites where LP-BER proceeds.

Cerebral Cavernous Malformation 2, also known as CCM2 is a piece of the CCM signaling pathway which is a vital regulator of heart and vessel formation as well as integrity. CCM2 performs through the stabilization of endothelial cell junctions. In addition, CCM2 functions as a scaffold protein for MAP2K3-MAP3K3 signaling. CCM2 plays a key role in the modulation of MAP3K3-dependent p38 activation induced by hyperosmotic shock. Mutations in CCM2 result in cerebral cavernous malformations. Multiple transcript variants encoding dissimilar isoforms have been discovered for CCM2.

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.

REG protein was shown to be stimulated during the regeneration of pancreatic islets. Since then, many Reg-related proteins have been identified in humans and other animals. In human, the four REG family genes, i.e., REG 1 alpha, REG 1 beta, REG-related sequence (RS) and HIP/PAP, have so far been isolated. These Reg-related proteins are classified into four subfamilies according to their amino-acid sequences, but they share a similar structure and physiological function. Reg protein is a growth factor for pancreatic beta cells and also suggests that the administration of Reg protein could be used as another therapeutic approach for diabetes mellitus. Human REG cDNA which encodes a 166-amino acid protein with a 22-amino acid signal peptide. The amino acid sequence of human REG protein has 68% homology to that of rat Reg protein.
Reg I was found to be expressed mainly in pancreatic beta and acinoductular cells as well as gastric fundic enterochromaffin-like (ECL) cells. Reg I production in ECL cells is stimulated by gastrin, as well as by the proinflammatory cytokine, cytokine-induced neutrophil chemoattractant (CINC)-2Beta. In patients with chronic hypergastrinemia, Reg production is stimulated, with the increased proliferation of gastric mucosal cells. Patients with Helicobacter pylori infection also showed increased Reg production in the gastric mucosa, partly via increased plasma gastrin concentration and partly via increased proinflammatory cytokine production. The serum concentration of the reg-protein was significantly higher in patients with various pancreatic diseases than in normal controls, and was also significantly higher in patients with acute pancreatitis or chronic relapsing pancreatitis than in patients with chronic pancreatitis. Furthermore, the serum PSP/reg-protein concentration was also significantly increased in liver cirrhosis, choledocholithiasis, and various cancers of the digestive system.

CIAO1 is a vital component of the cytosolic iron-sulfur (Fe/S) protein assembly machinery. CIAO1 protein is required for the maturation of extra mitochondrial Fe/S proteins and seems to specifically modulate the trans-activation activity of WT1. CIAO1 participates in chromosome segregation as a part of the mitotic spindle-associated MMXD complex.

Nephroblastoma Overexpressed (NOV) which is encoded by the NOV gene is a part of the CCN (CTGF/CYR61/NOV) family. NOV takes part in reducing tumorgenicity and proliferation of certain cancer cell lines. NOV interacts with numerous proteins and is involved in both internal and external cell signaling. NOV is expressed in particular tumors, including Wilm’s tumor and most nephroblastomas and is also exerts proangiogenic activities.

rRNA-processing protein UTP23 homolog (UTP23) is a small subunit (SSU) processome component. The SSU processome is a complex involved in ribosome biogenesis and essential for pre-18S rRNA maturation. UTP23 is vital for the first 3 cleavage steps in 18S rRNA maturation. Furthermore, single-point mutations in the conserved putative active site of Utp24 but not Utp23 annul its function in ribosome biogenesis.

PEX19 is vital for peroxisome biogenesis in Saccharomyces cerevisiae. PEX19 is limited to the outer surface of peroxisomes in liver cells and is has a part in the early stage of peroxisome membrane assembly, prior to the import of matrix protein.