Questions, Feedback & Help
Send us an email and we'll get back to you ASAP. Or you can read our Frequently Asked Questions.

WormBase Tree Display for WBProcess: WBbiopr:00000081

expand all nodes | collapse all nodes | view schema

Name Class

WBbiopr:00000081Public_namemiRNA pathway
SummarymicroRNA (miRNA) elements are short (20-25 nucleotides (nt)), noncoding, single-stranded RNAs that bind to complementary sequences on target messenger RNA (mRNAs), which can result in translational repression or target mRNA degradation. microRNAs are critical components of developmental timing, responses to stress, and aging. Regulating the biogenesis and metabolism of miRNAs thus has an enormous impact on the health of the organism. In the genome, miRNAs reside in intergenic regions as well as within introns and exons of protein-coding genes. miRNAs are transcribed as long primary miRNAs (pri-miRNA). These pri-miRNA transcripts form hairpin-like structures with a double stranded stem and a terminal loop. pri-miRNAs are cleaved into smaller ~65-nt long precursor miRNA (pre-miRNA) by terminal-loop binding proteins and a microprocessor complex. This complex is composed of DRSH-1/DROSHA and PASH-1/DGCR8. In humans and yeast, the pre-miRNA product is exported to the cytoplasm by Exportin-5/XPO5 and RanGTP, respectively. The closest homologs of these proteins in C. elegans include xpo-1 and Y105E8A.1/yrs-2. Once in the cytoplasm, the pre-miRNA is cleaved at the top of the terminal loop by DCR-1/DICER, producing a duplex of two mature ~22nt miRNAs.An alternative, DRSH-1/DROSHA-independent, miRNA biogensis pathway has been identified in C. elegans and Drosophila. In this pathway pre-miRNAs are created through mRNA spliced introns. These introns form Mirtron lariats, which are debranched and refolded into pre-miRNA species. Mirtron generated pre-miRNAs are exported and processed in the same way as pre-miRNAs generated through the canonical miRNA biogenesis pathway. As mentioned previously, miRNA activity functions in many biological processes and hence needs to be temporally and spatially regulated. Much of that regulation occurs at the level of miRNA biogenesis and processing through Drosha binding/associated proteins, Dicer binding proteins, or proteins that bind to pri- and/or pre-miRNAs terminal loops. These regulators control expression or activity of miRNAs on specific miRNAs or families of miRNAs. For example, DCR-1 interaction proteins, ALG-1 and ALG-2, are required for lin-4 and let-7 miRNA formation and maturation. miRNA processing can also be influenced by ADAR editing, cellular localization, proteins known to regulate transcription (such as p53, SMADs) and proteins known to regulate mRNA stability (such as KSRP).
Other_namemicroRNA pathway
miRNA biogenesis
miRNA metabolism
Related_topicSpecialisation_ofWBbiopr:00000037
Involved_entityGene (16)
Interaction (12)
MoleculeWBMol:00004697Paper_evidenceWBPaper00040868
Associated_withPhenotypeWBPhenotype:0001371Paper_evidenceWBPaper00029211
WBPhenotype:0001373Paper_evidenceWBPaper00029211
WBPhenotype:0001779
GO_termGO:2000631
GO:2000634
GO:0035196
PathwayDB_infoDatabaseWikiPathwaysPathwayWP394
Remark"WikiPathways" "Pathway" "WP394"
ReferenceWBPaper00005043
WBPaper00005105
WBPaper00005192
WBPaper00005601
WBPaper00006293
WBPaper00006373
WBPaper00024225
WBPaper00024573
WBPaper00026707
WBPaper00026713
WBPaper00026743
WBPaper00026761
WBPaper00027057
WBPaper00029181
WBPaper00029211
WBPaper00029229
WBPaper00030805
WBPaper00030856
WBPaper00031031
WBPaper00031224
WBPaper00031252
WBPaper00032074
WBPaper00032117
WBPaper00032160
WBPaper00032187
WBPaper00032458
WBPaper00032489
WBPaper00032516
WBPaper00032974
WBPaper00034755
WBPaper00035168
WBPaper00035291
WBPaper00035316
WBPaper00036027
WBPaper00036036
WBPaper00036130
WBPaper00036213
WBPaper00036450
WBPaper00036657
WBPaper00037756
WBPaper00037823
WBPaper00037938
WBPaper00038129
WBPaper00038153
WBPaper00038224
WBPaper00038356
WBPaper00039818
WBPaper00039920
WBPaper00040065
WBPaper00040075
WBPaper00040280
WBPaper00040322
WBPaper00040559
WBPaper00040584
WBPaper00040724
WBPaper00040868
WBPaper00040876
WBPaper00040890
WBPaper00040911
WBPaper00041168
WBPaper00041218
WBPaper00041416
WBPaper00041520
WBPaper00041677
WBPaper00041742
WBPaper00041947
WBPaper00041977
WBPaper00042035
WBPaper00042195
WBPaper00042320
WBPaper00042410
WBPaper00043989
WBPaper00044681
WBPaper00045183
WBPaper00045275
WBPaper00045501
WBPaper00045911
WBPaper00046042