ClassificationThis section has been translated automatically.
- RNase1: RNase1, also Ribonuclease A Family Member 1, is a pancreatic-type secretory ribonuclease, a subgroup of the ribonuclease A superfamily. The encoded endonuclease cleaves internal phosphodiester RNA bonds on the 3' side of pyrimidine bases. It prefers poly(C) as a substrate and hydrolyzes 2',3'-cyclic nucleotides with a pH optimum near 8.0. The enzyme is monomeric and more commonly serves to degrade ds-RNA relative to ss-RNA. Mutations in the associated gene are associated with mesothelioma and Lynch syndrome....
- Rnase2 (EDN): eosinophil-derived neurotoxin (EDN) is an enzyme that in humans is encoded by the RNASE2 gene. It is found in eosinophil granulocytes and is closely related to the eosinophil cationic protein (RNASE3), from which it split about 50 million years ago after the split between Old World monkeys and New World monkeys. RNase3 has cytotoxic properties and is able to reduce the activity of single-stranded RNA viruses in cultures through its enzymatic activity. It also serves as an attractant for immune cells.
- RNase3(ECP): the cationic protein of eosinophils, also known as ECP is a cytotoxic and neurotoxic protein with a molecular weight of 21,000 daltons. ECP is found almost exclusively in eosinophil granulocytes and is released only by activated eosinophils during the late phase of the allergic reaction. Thus, the concentration of ECP in serum and other body fluids correlates quantitatively with the degree of activation of these cells. An increase in ECP concentration is found in a variety of inflammatory processes, such as bronchial asthma, atopic dermatitis, rhinitis, allergic inflammation of the eye, parasitic infections, inflammatory bowel disease. Treatment with anti-inflammatory drugs leads to both improvement of clinical symptoms of patients and reduction of seasonally elevated levels of circulating ECP. Therefore, ECP can be used in asthmatics as a sensitive marker to assess disease activity and monitor therapy.
- RNase 4: The enzyme is an intracellular and plasma enzyme first isolated from a colon adenocarcinoma cell line. It is found in the pancreas, saliva and liver and has a similar distribution pattern to angiogenin (RNase5). RNase4 plays an important role in mRNA cleavage and exhibits marked specificity toward the 3' side of uridine nucleotides. RNase 4 is coexpressed and shares the same promoter with angiogenin (ANG).
- RNase 5 (Angiogenin) Angiogenin is a member of the RNase A superfamily but has relatively weak ribonucleolytic activity. Angiogenin is a potent mediator of new blood vessel formation. Angiogenin also accumulates in the nucleolus, where it stimulates ribosomal transcription. Under stress conditions, this protein migrates to the cytosol, where it hydrolyzes cellular tRNAs and affects protein synthesis. This protein has been shown to be both neurotrophic and neuroprotective, and the mature protein exhibits antimicrobial activity against various bacteria and fungi, including S. pneumoniae and C. albicans. Due to its effect on rRNA production and angiogenesis, this gene plays an important role in cell growth and tumor progression.
- RNase 6: Ribonuclease 6 shows a preference for the pyrimidines uridine and cytosine. Demonstrated potent antibacterial activity against a range of Gram-positive and Gram-negative bacteria, including P.aeruginosa, A.baumanii, M.luteus, S.aureus, E.faecalis, E.faecium, S.saprophyticus and E.coli. Leads to loss of bacterial membrane integrity and also promotes agglutination of Gram-negative bacteria. The enzyme probably contributes to urinary tract sterility.Bactericidal activity is independent of RNase activity.
- RNase 7 (RNase of the skin): Ribonuclease 7, also called "Skin-Derived Antimicrobial Protein 2," belongs to the pancreatic ribonuclease family of a subgroup of the ribonuclease A superfamily. RNase 7 is the dominant RNase of the skin and one of the AMPs with the broadest spectrum of activity. It has broad-spectrum antimicrobial activity against bacteria and fungi. The enzyme is constitutively expressed and is self-inducible. These diverse properties make RNase 7 a very interesting AMP for research and possibly for the future development of new therapeutic strategies. Several papers suggest that RNase 7 probably plays an important role in the defense against germs during infection or inflammation in the skin. RNase 7 is also expressed in other tissues, with mRNA expression being most pronounced in the respiratory and urinary tracts. Recent evidence suggests that RNase 7 is also one of the major AMPs expressed in joints, oral cavity, cornea, and basal epithelial cells of the respiratory tract.
- RNase 8 (RNase of placenta): The gene encoding ribonuclease 8 is preferentially expressed in placenta. It cannot be detected in any other tissue studied. Phylogenetic analysis suggests that RNase 7 is the closest relative of RNase 8 and that the pair likely results from a gene duplication event in primates. The ribonucleolytic activity of recombinant human RNase 8 is rather low. It does not exhibit antiviral or antibacterial activities characteristic of other RNase A ribonucleases. The tissue-specific expression of RNase 8 suggests a unique physiological function.
LiteratureThis section has been translated automatically.
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