TRANSCRIPTION OF 4 SATELLITE DNA SUBFAMILIES IN DIPRION PINI (HYMENOPTERA, SYMPHYTA, DIPRIONIDAE)

Four satellite DNA subfamilies Ps, Pv, Pv65 and Ec, resulting from the evolution of a common ancestral motif, were isolated and characterize d in the genomic DNA of Diprion pini, a phytophagous of Pinus sylvestr is. Consensus sequences were 148-312 bp long, Sequence analyses reveal ed that these satellite subfamilies have evolved from a 45-bp ancestra l motif. The amounts of each satellite in the genome (0-10%) and the a ccessibility of the DNA to restriction enzymes were sex dependent, The migration of each monomer in polyacrylamide gels and the electrophore tic migration of d(AT(n greater than or equal to 3)) residues showed t hat all four satellite subfamilies are curved. Their transcription was analyzed using reverse transcription and the polymerase chain reactio n. Three satellite DNA subfamilies were transcribed on both strands, a nd in both sexes. However, the female satellite DNAs seem to be more a ctively transcribed than those of males, indicating that transcription is not constitutive. The lack of:any significant open reading frame i n satellite monomers indicates that the RNA may function as structural or catalytic RNA rather than encoding protein.