Comparative Cytogenetics of the Congo African Grey Parrot (Psittacus erithacus)

Abstract

The Congo African grey parrot (Psittacus erithacus, PER) is an endemic species of Central Africa, valued for its intelligence and listed as vulnerable due to poaching and habitat destruction. Improved knowledge about the P. erithacus genome is needed to address key biological questions and conservation of this species. The P. erithacus genome was studied using conventional and molecular cytogenetic approaches including Zoo-FISH. P. erithacus has a ‘typical' parrot karyotype with 2n = 62-64 and 8 pairs of macrochromosomes. A distinct feature was a sharp macro-microchromosome boundary. Telomeric sequences were present at all chromosome ends and interstitially in PER2q, the latter coinciding with a C-band. NORs mapped to 4 pairs of microchromosomes which is in contrast to a single NOR in ancestral type avian karyotypes. Zoo-FISH with chicken macrochromosomes GGA1-9 and Z revealed patterns of conserved synteny similar to many other avian groups, though neighboring synteny combinations of GGA6/7, 8/9, and 1/4 were distinctive only to parrots. Overall, P. erithacus shared more Zoo-FISH patterns with neotropical macaws than Australian species such as cockatiel and budgerigar. The observations suggest that Psittaciformes karyotypes have undergone more extensive evolutionary rearrangements compared to the majority of other avian genomes.

Chromosome Painting in <b><i>Trogon s. surrucura</i></b> (Aves, Trogoniformes) Reveals a Karyotype Derived by Chromosomal Fissions, Fusions, and Inversions

“…6 E). Interestingly, the association GGA6/GGA7/microchromosome has also been reported in some species of Psittaciformes ( Agapornis roseicollis , Ara macao , Psittacus erithacus , Ara chloropterus, and Anodorhynchus hyacinthinus ) [Nanda et al, 2007;Seabury et al, 2013;de Oliveira Furo et al, 2015;Seibold-Torres et al, 2015]. However, in this group, the order in the chromosome is inverted compared to TSU4, with GGA7 being terminal and GGA6 interstitial.…”

Phylogenetic Analysis and Karyotype Evolution in Two Species of Core Gruiformes: Aramides cajaneus and Psophia viridis

“…The association GGA6/GGA7 has been found in two species of family Rallidae (F. atra and G. chloropus) [17] and family Psophiidae (P. viridis); however, it is absent in A. cajaneus ( Table 1). The association between GGA6/GGA7 has been detected in five species belonging to different orders of birds: Galliformes-Numida meleagris [21], Strigiformes-Pulsatrix perspicillata [22], Trogoniformes-Trogon s. surrucura [23], Psittaciformes-Nymphicus hollandicus, Agapornis roseicollis, Melopsittacus undulates [24], Ara macao [25], Ara chloropterus, Anodorhynchus hyacinthinus [9], Psittacus erithacus [26], Pyrrhura frontalis, Amazona aestiva [11] and Columbiformes-Leptotila verreauxi [16]. Hence, GGA6/GGA7 association originated independently in five different orders.…”

Chromosome Level Genome Assembly and Comparative Genomics between Three Falcon Species Reveals an Unusual Pattern of Genome Organisation

“…Falconidae and Accipitridae, together with Psittaciformes members, are recognized as avian species with 'atypical' karyotypes and previous studies have shown that these avian species have the highest numbers of rearrangements occurring on their macrochromosomes [17,[30][31][32]. Recent studies conducted on such 'atypical' karyotype species collectively highlight the substantial amount of rearrangements of macrochromosomes that have occurred throughout their evolutionary history.…”