DCL1

DCL1 (an abbreviation of Dicer-like 1) is a gene in plants that codes for the DCL1 protein, a ribonuclease III enzyme involved in processing microRNA (miRNA). Although DCL1 is named for its homology with the metazoan protein Dicer, its role in miRNA biogenesis is somewhat different, due to substantial differences in miRNA maturation processes between plants and animals. Unlike Dicer, DCL1 is localized to the cell nucleus, where it initiates miRNA processing as the catalytic component of the so-called Dicing complex, which also contains HYL1, a double-stranded RNA binding protein, and a zinc-finger protein known as SE or SERRATE. Within the nucleus, Dicing complexes co-localize in Dicing bodies or D-bodies. In plants, DCL1 is responsible both for processing a primary miRNA to a pre-miRNA, and for then processing the pre-miRNA to a mature miRNA. In animals, the equivalents of these two steps are carried out by different proteins; pri-miRNA processing takes place in the nucleus by the ribonuclease Drosha as part of the Microprocessor complex, and processing to a mature miRNA takes place in the cytoplasm by Dicer to yield a mature miRNA.

Although DCL1 is responsible for the majority of the miRNA processing in plants, most plants contain an additional three members of the same family (DCL2, DCL3, DCL4) with related roles in RNA processing.