The Isolation, Cloning, Characterization and Conservation among the Psittacidae of a Sex-Specific, Tandemly Repeated DNA Component from the African Grey Parrot (Psittacus erithacus)

Abstract

Digestion of DNA of the female African grey parrot (Psittacus erithacus) with the restriction endonuclease Msp1 revealed the presence of a tandemly repeated, female-specific component with a repeat monomer length of approx. 628 nts and a repeat copynumber of approx. 1.3 x 10 4 . The nucleotide sequence of a cloned 628 bp repeat monomer, is characterized by short oligo dA2-6 segments which occur with an average periodicity of 10.5 bp. The sequence shows therefore some similarity with the W-specific repeat of the chicken, which is characterized by alternating dT3-5 and dA3-5 oligonucleotides occurring each with a periodicity of 21 bp. Similar to the chicken sequence the psittacine monomers show a strong reduction in electrophoretic mobility in polyacrylamide gels. The component occurs widespread in females of many members of different subfamilies of the Psittacidae. Minor amounts of cross hybridizing material were found in males of most species tested. Only in a few species, including the Eclectus parrot (Eclectus roratus) and the Bourke’s parakeet (Neopsephotus bourkii), DNA of males contained, in addition to an abundant female specific component, significant amounts of non-sex-specific PARsex-1Arch Vet Sci Med 2022; 5 (2):004-023 DOI: 10.26502/avsm.032 Archives of Veterinary Science and Medicine 5 like material, whereas DNA of male and female keas (Nestor notabilis) contains almost nothing.