| miR-33a | |
| Symbol: | miR-33a |
| Altsymbols: | mir33a |
| Rfam: | RF00667 |
| Mirbase: | MI0000091 |
| Mirbase Family: | MIPF0000070 |
| Rna Type: | miRNA |
| Tax Domain: | Metazoa |
| Go: | 0035195 |
| So: | 0001244 |
| Entrezgene: | 407039 |
| Hgncid: | 31634 |
| Chromosome: | 22 |
| Arm: | q |
| Band: | 13.2 |
| miR-33b | |
| Symbol: | miR-33b |
| Altsymbols: | mir33b |
| Rfam: | RF00667 |
| Mirbase: | MI0003646 |
| Mirbase Family: | MIPF0000070 |
| Rna Type: | miRNA |
| Tax Domain: | Metazoa |
| Go: | 0035195 |
| So: | 0001244 |
| Entrezgene: | 693120 |
| Hgncid: | 32791 |
| Chromosome: | 17 |
| Band: | 13.2 |
miR-33 is a family of microRNA precursors, which are processed by the Dicer enzyme to give mature microRNAs.[1] miR-33 is found in several animal species, including humans. In some species there is a single member of this family which gives the mature product mir-33. In humans there are two members of this family called mir-33a and mir-33b, which are located in intronic regions within two protein-coding genes for Sterol regulatory element-binding proteins (SREBP-2 and SREBP-1) respectively.[2]
miR-33 plays a role in lipid metabolism; it downregulates a number of ABC transporters, including ABCA1 and ABCG1, which in turn regulate cholesterol and HDL generation.[3] [4] Further related roles of miR-33 have been proposed in fatty acid degradation and in macrophage response to low-density lipoprotein.It has been suggested that miR-33a and miR-33b regulates genes Involved in fatty acid metabolism and insulin signalling.[5]
Potential binding sites for mir-33 have been identified in the cDNA of tumour suppressor p53.[6] Further, study has shown that miR-33 is able to repress p53 expression and p53-induced apoptosis. This function is thought to be related to hematopoietic stem cell renewal.[7]
miR-33, along with miR-122, could be used to diagnose or treat conditions related to metabolic disorders and cardiovascular disease.[8]