Search results

Rnase P protein, AKA rnpA, is an important enzyme consisting of the C5 protein (which encoded by rnpA) and the catalytic M1 RNA (encoded by rnpB) subunits. rnpA is ribonucleoprotein that catalyzes the removal of the 50- leader elements of precursor tRNAs and generates the mature 50-end of tRNAs. This step is critical for theformation of functional tRNA molecules in bacteria, archaea and eukarya. More importantly, it has lately been established that RNase P is essential for the endonucleolytic separation of certain polycistronic tRNA transcripts such as valV valW, leuQ leuP leuV and secG leuU. Therefore, it was hypothesized that the essential function of RNase P might be related to the complete absence of a particular tRNAthat was dependent on the enzyme for initial separation from polycistronic transcripts.

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.

DDX39A which is a part of the DEAD box protein family is characterized by the conserved motif Asp-Glu-Ala-Asp. This pattern is implicated in a various cellular processes involving alteration of RNA secondary structure, nuclear and mitochondrial splicing, and ribosome and spliceosome assembly. Several members of the DEAD box protein family are taking part in embryogenesis, spermatogenesis, and cellular growth and division.

Ribonuclease H2 subunit A (RNASEH2A) is a member of the RNase HII family and eukaryotic subfamily. RNASEH2A Plays a part in DNA replication, probably by mediating the removal of lagging-strand Okazaki fragment RNA primers throughout DNA replication. RNASEH2A catalyzes the endonucleolytic cleavage of RNA to a 5’-phosphomonoester and is capable to bind magnesium or manganese as cofactors. Aicardi-Goutieres syndrome type 4 (AGS4) caused by defects in RNASEH2A.

TCEB1 (elongin C) is a subunit of elongin, which is a common transcription elongation factor that increases the RNA polymerase II transcription elongation past template encoded arresting sites. The SIII complex is comprised of elongins A/A2, B and C. The SIII complex activates elongation by RNA polymerase II by curbing transient pausing of the polymerase at numerous sites within transcription units. Elongin A acts as the transcriptionally active component of the SIII complex, while elongins B and C are regulatory subunits. Elongin A2 is specifically expressed in the testis, and able to forming a stable complex with elongins B and C. The VHL (von Hippel-Lindau) tumor suppressor protein binds to elongins B and C, and thus inhibits transcription elongation.

REXO1 is an exonuclease domain-containing protein which binds to Elongin. The Elongin complex stimulates the rate of transcription elongation by RNA polymerase II by suppressing the transient pausing of the polymerase at many sites along the DNA template. REXO1 is composed of 1221 amino acids and its mRNA is ubiquitously expressed. REXO1 is a putative stem cell marker and is highly expressed in embryonic and adult stem cells.

SNUPN is a nuclear import adaptor protein which is part of the Snurportin family.
SNUPN is Localized to the cytoplasm and nucleus and contains an N-terminal IBB domain and a trimethylguanosine (m3G)-cap binding domain. SNUPN binds specifically the terminal 2,2,7-m3G-cap at the 5'' end of U snRNPs and is involved in transport of U snRNPs into the nucleus through an association with Importin β.

Ribonuclease 1R (NASE1) is a small protein which is a part of pancreatic ribonuclease enzyme family. NASE1 has 4 disulfide bonds in its native state and cleaves speciallyafter pyrimidine nucleotides.Cleavage takes place in 2 steps: first, the 3’,5’-phosphodiester bond is cleaved to craete a 2’,3’-cyclic phosphodiester intermediate; than, the cyclic phosphodiester is hydrolyzed to a 3’-monophosphate. NASE1is activated the most with single stranded RNA.NASE1inhibited by alkylation of His12 and His119 and activated by potassium and sodium salts.NASE1hydrolyzes RNA from protein samples.

Cold inducible RNA-binding protein (CIRBP) has a protective role in the genotoxic stress response by stabilizing transcripts of genes involved in cell survival. CIRBP localizes to the nucleus and contains one RRM (RNA recognition motif) domain. Expressed ubiquitously, CIRBP is believed to play a crucial role in the suppression of cellular proliferation in response to UV irradiation or extreme cold.

General Transcription Factor IIF Polypeptide 2 (GTF2F2) is a general transcription initiation factor which binds to RNA polymerase II and helps engage it in the initiation complex in collaboration with TFIIB. GTF2F2 promotes transcription elongation. GTF2F2 shows ATP-dependent DNA-helicase activity.

FtsJ RNA Methyltransferase Homolog 2 (FTSJ2) belongs to the S-adenosylmethionine-binding protein family. FTSJ2 is a nucleolar protein and which is involved in cell cycle control and DNA repair and the processing and modification of rRNA. FTSJ2 is extensively expressed, with the highest expression in the muscle, placenta, and heart.

Polymerase Delta 4 also known as POLD4 is the smallest subunit of DNA polymerase delta. DNA polymerase delta which takes a vital part in DNA replication and repair possesses both polymerase and 3' to 5' exonuclease activity. POLD4 increases the activity of DNA polymerase delta and takes a part in fork repair and stabilization during interactions with the DNA helicase Bloom syndrome protein. POLD4 contributes to PCNA-dependent activity of DNA polymerase delta.

Nucleosome Assembly Protein 1-Like 4 (NAP1L4) is a part of the nucleosome assembly protein (NAP) family which interacts with both core and linker histones. NAP1L4 plays a role as a histone chaperone due to his ability to shuttle between the cytoplasm and nucleus. NAP1L4 modulates transcriptional activation by target nuclear receptors. NAP1L4 is one of several located near the imprinted gene domain of 11p15.5 which is an important tumor-suppressor gene region.

Mitochondrial methylglutaconyl-CoA hydratase (AUH) is involved in the amino acid degradation pathway by catalyzing the conversion of 3-methylglutaconyl-CoA to 3-hydroxy-3-methylglutaryl-CoA and water. AUH Human is expressed as a single mRNA species of 1.8 kb, and translated as a 40kDa precursor protein which is consequently processed to a 32kDa mature form. AUH has a very low enoyl-CoA hydratase activity. The AUH protein binds to the AU-rich element (ARE), which is a common element found in the 3' UTR of rapidly decaying mRNA such as c-fos, c-myc and granulocyte/ macrophage colony stimulating factor. AU-rich elements are involved in directing RNA to rapid degradation and deadenylation. In addition, AUH is homologous to enol-CoA hydratase, which is an enzyme involved in fatty acid degradation, and has been shown to have intrinsic hydratase enzymatic activity. AUH is therefore a bifunctional chimera between RNA binding and metabolic enzyme activity.

ElaC Ribonuclease Z 1, also known as ELAC1 is a member of the RNase Z family. Zinc phosphodiesterase, which shows some tRNA 3'-processing endonuclease activity. In addition, ELAC1 is implicated in tRNA maturation, by removing a 3'-trailer from precursor tRNA.

Streptavidin is a tetrameric protein secreted by Streptomyces avidinii which binds firmly to biotin. Streptavidin is widely used in molecular biology through its unique high affinity for the vitamin biotin. The dissociation constant (Kd) of the biotin-streptavidin complex is about ~10-15 mol/L. The strong affinity recognition of biotin and biotinylated molecules has made streptavidin one of the most important components in diagnostics and laboratory kits. The streptavidin/biotin system has one of the biggest free energies of association of yet observed for noncovalent binding of a protein and small ligand in aqueous solution (K_assoc = 10**14). The complexes are also extremely stable over a wide range of temperature and pH.

RNA Binding Motif Protein 11 (RBM11) which contains 1 RNA recognition motif is a part of the RBM family. The RBM gene family encodes proteins with an RNA binding motif which participate in the modulation of apoptosis. RBM11 is expressed in testis, kidney, spleen, brain, spinal cord and mammary gland and can be found as 2 isoforms produced by alternative splicing.

CTD small phosphatase-like protein (CTDSPL) specially catalyzes the dephosphorylation of 'Ser-5' within the tandem 7 residues repeats in the C-terminal domain (CTD) of the biggest RNA polymerase II subunit POLR2A. CTDSPL negatively regulates RNA polymerase II transcription, probably by directing the transition from initiation/capping to processive transcript elongation. CTDSPL is employed by REST to neuronal genes which contain RE-1 elements, directing to neuronal gene silencing in non-neuronal cells.

SNRPE facilitates the cytoplasmic construction of the UsnRNPs by binding to a conserved Sm site on UsnRNA and forming a stable snRNP core complex. While a core protein to UsnRNP, the SNRPE connects with the entire U family of snRNAs including U1–U6. In addition, SNRPE interacts with DDX20 and Small nuclear ribonucleoprotein polypeptide F.

Mediator Complex Subunit 27 (MED27) is a subunit of the CRSP (cofactor required for SP1 activation) complex, which, together with TFIID, is necessary for efficient activation by SP1. MED27 is a component of the Mediator complex, a coactivator involved in the regulated transcription of virtually all RNA polymerase II-dependent genes. MED27 protein is also a component of other multisubunit complexes such as the thyroid hormone receptor-(TR-) associated proteins which interact with TR and facilitate TR function on DNA templates in conjunction with initiation factors and cofactors. The activation of MED27 gene transcription is a multistep process, which is triggered by factors that identify transcriptional enhancer sites in DNA.

SNRPC is a member of the U1 small nuclear ribonucleoprotein C family. The SNRPC protein component of the U1 small nuclear ribonucleoprotein (snRNP) particle required for the formation of the spliceosome. SNRPC participates in the processing of nuclear precursor messenger RNA splicing. snRNP particles are tackled by autoantibodies frequently produced by patients with connective tissue diseases.

RNA 3'-Terminal Phosphate Cyclase (RTCA) encodes a part of the RNA 3'-phosphate cyclase family. RTCA takes part in RNA metabolism by catalyzing the ATP-dependent conversion of the 3'-phosphate of RNA substrates to a 2',3'-cyclic phosphodiester. RTCA is involved in some phases of cellular RNA processing.

Ribophorin 2 (RPN2) is a dolichyl-diphosphooligosaccharide protein glycosyltransferase subunit 2. The Ribophorin 2 protein is part of an N-oligosaccharyl transferase complex which links high mannose oligosaccharides to asparagine residues found in the Asn-X-Ser/Thr consensus motif of nascent polypeptide chains. RPN2 is analogous in sequence to the yeast oligosaccharyl transferase subunit SWP1.

Ribonuclease 7 (RNASE7) is one of the final RNase A superfamily ribonucleases. RNASE7 was isolated from skin-derived stratum corneum. RNASE7 protein demonstrated potent ribonuclease activity and hence may contribute to the well-known ribonuclease activity of human skin. RNASE7 has revealed a broad spectrum antimicrobial activity against many pathogenic microorganisms and extraordinarily potent activity.