Structural analysis of the fibroin gene at the 5′ end and its surrounding regions

摘要: Abstract Using the genomic clones of fibroin gene with its flanking sequences, a detailed restriction map was prepared particular attention given to region neighboring 5′ end gene. About 60% mRNA has complete cap (m 7 GpppAmUmCXG), and remaining 40% an unmethylated (GpppAPyXXG). The latter can be radioactively labeled by use vaccinia capping enzymes. mRNA, we mapped hybridization enzyme digests. DNA sequencing this revealed sequence ATCAGCATCAG that corresponds APyXXG in tandem. also located these 11 nucleotides. Since second ATCAG protected from S1 digestion following total have tentatively assigned it as sole transcription unit. 700 bp were sequenced −800 +1700 bp. about 210 preceding which may accommodate promoter is very AT-rich contains clusters A T residues. This statistically significant dyad symmetries, direct repeats inverted repeats. At −30 −24, TATAAAA observed, similar Pribnow-type (TAT G ATG). codes for gly-ala repetitious peptide characteristic begins somewhere between 1340 1600 end. An intervening 1.1 kb interrupts 70 detected R loop formation. Structures cloned producing nonproducing cells look same, especially around region.