Low temperature causes accumulation of unspliced fibroin mRNA precursor molecules in silkworm larvae.
Silk fibroin premessenger mRNA is a large (17 kb) molecule containing a single intron. Previous S1 mapping studies yielded evidence of processing cleavages at sites within the intron, in addition to the major cleavages at the intron/exon boundaries. We have performed S1 mapping experiments using RNA from animals which had been incubated at low temperature. These experiments show a marked accumulation of full-length fibroin mRNA precursor relative to controls, and a reduction in the abundance of molecules lacking portions of the intron. These results demonstrate a partial uncoupling of transcription and splicing in vivo.
D000818:Animals; D001483:Base Sequence; D012831:Bombyx / Q000235:genetics*; D002874:Chromosome Mapping; D003080:Cold Temperature; D005349:Fibroins / Q000235:genetics*; D007814:Larva / Q000378:metabolism; D011498:Protein Precursors / Q000378:metabolism*; D012323:RNA Processing, Post-Transcriptional; D012326:RNA Splicing; D012333:RNA, Messenger / Q000378:metabolism*
D011498:Protein Precursors; D012333:RNA, Messenger; D005349:Fibroins