A family of U1 pseudogenes in Bombyx mori may be derived from an ancestral pseudogene.
Seven EMBL-4 lambda clones containing U1 small nuclear RNA sequences were isolated from a Bombyx mori genomic library. Six of the seven represent unique sequences. The six unique U1 sequences exhibit fixed point 3'-end truncation. Five out of the six clones share immediate 3'-end flanking sequences while two share 5'-end flanking sequences. Fixed point 3'-end truncation and a hierarchy of shared to unique diagnostic mutations may suggest a family of U1 pseudogenes generated from a reverse-transcribed class II pseudogene in B. mori. An ancestral 'master' U1 pseudogene capable of RNA- and/or DNA-mediated transposition may give rise to generations of U1 pseudogenes that include the original pseudogene's flanking sequences. Identical 3'-end truncation in some of these U1 sequences can be explained by RNA self-priming due to intra-strand binding prior to reverse transcription.
Vega
L R
LR
Department of Biological Sciences, Florida International University, Miami 33199.
Amengual
J
J
Herrera
R J
RJ
D000818:Animals; D001483:Base Sequence; D012831:Bombyx / Q000235:genetics*; D003001:Cloning, Molecular; D004247:DNA / Q000235:genetics; D017931:DNA Primers / Q000235:genetics; D017344:Genes, Insect; D015698:Genomic Library; D008957:Models, Genetic; D008969:Molecular Sequence Data; D009154:Mutation; D011544:Pseudogenes; D012342:RNA, Small Nuclear / Q000235:genetics*; D012689:Sequence Homology, Nucleic Acid; D014158:Transcription, Genetic
D017931:DNA Primers; D012342:RNA, Small Nuclear; D004247:DNA