2j7n: Difference between revisions

RNA silencing refers to a group of RNA-induced gene-silencing mechanisms, that developed early in the eukaryotic lineage, probably for defence, against pathogens and regulation of gene expression. In plants, protozoa, fungi, and nematodes, but apparently not insects and vertebrates, it, involves a cell-encoded RNA-dependent RNA polymerase (cRdRP) that produces, double-stranded RNA triggers from aberrant single-stranded RNA. We report, the 2.3-A resolution crystal structure of QDE-1, a cRdRP from Neurospora, crassa, and find that it forms a relatively compact dimeric molecule, each, subunit of which comprises several domains with, at its core, a catalytic, apparatus and protein fold strikingly similar to the catalytic core of the, DNA-dependent RNA polymerases responsible for transcription. This, evolutionary link between the two enzyme types suggests that aspects of, RNA silencing in some organisms may recapitulate transcription/replication, pathways functioning in the ancient RNA-based world.

2J7N is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Neurospora_crassa Neurospora crassa] with MG and GOL as [http://en.wikipedia.org/wiki/ligands ligands]. Structure known Active Site: AC1. Full crystallographic information is available from [http://ispc.weizmann.ac.il/oca-bin/ocashort?id=2J7N OCA].  

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