title: Evidence that populations of Dictyostelium single-copy mRNA transcripts carry common repeat sequences.
abstract: Two recombinant plasmids, M4 and KH10, carrying Dictyostelium DNA inserted into the Eco RI restriction endonuclease site of pMB9 by poly(dA)-poly(dT) tailing, were selected for study because they are complementary to abundant mRNA populations from Dictyostelium. Both plasmids have been shown to hybridize a heterogeneous size class of mRNAs which, in the case of KH10, comprise 5-10% of the pulse-labeled poly(A)+ RNA from vegetative cells. Analysis of the sequence organization of the two pieces of Dictyostelium DNA shows that they consist mostly of single-copy sequences with a short DNA sequence which is repeated in the genome and interspersed with single-copy DNA. These and other results suggest that the majority of the hybridization of pulse-labeled mRNA to M4 and KH10 is to the short "repeated" DNA sequences. In the genome, members of these repeat families appear to be transcribed onto a population of different single-copy mRNAs. Additional results show that M4 DNA contains a sequence which is entirely complementary to a discrete mRNA.
mesh_terms: D001483:Base Sequence; D004262:DNA Restriction Enzymes; D004274:DNA, Recombinant / Q000378:metabolism; D004023:Dictyostelium / Q000378:metabolism*; D007700:Kinetics; D009691:Nucleic Acid Denaturation; D009693:Nucleic Acid Hybridization; D010957:Plasmids; D011061:Poly A / Q000378:metabolism; D011067:Poly dA-dT; D012333:RNA, Messenger / Q000096:biosynthesis*; D014158:Transcription, Genetic
chemical_list: D004274:DNA, Recombinant; D012333:RNA, Messenger; D011061:Poly A; D011067:Poly dA-dT; D004262:DNA Restriction Enzymes