Identification and functional analysis of two U3 binding sites on yeast pre-ribosomal RNA.

摘要: Abstract It has long been known that U3 can be isolated hydrogen bonded to pre-ribosomal RNAs, but the sites of interaction are poorly characterized. Here we show yeast cross-linked 35S pre-rRNA both in deproteinized extracts and living cells. The cross-linking were localized 5' external transcribed spacer (ETS) then identified at nucleotide level. Two regions near end vivo vitro; evolutionarily conserved box A region a 10 (nt) sequence with perfect complementarity an ETS sequence. cross-links detected ETS, +470, within complementary U3, +655, close cleavage site 18S rRNA. tagged rDNA construct was used follow effects mutations vivo. small deletion around +470 prevents synthesis This is homologous vertebrate cleavage. We propose this may direct assembly processing complex required for cleavages generate