10.6084/m9.figshare.4750936.v1
Suárez-Villota E.Y.
Suárez-Villota
E.Y.
Pansonato-Alves J.C.
Pansonato-Alves
J.C.
Foresti F.
Foresti
F.
Gallardo M.H.
Gallardo
M.H.
Supplementary Material for: Homomorphic Sex Chromosomes and the Intriguing Y Chromosome of Ctenomys Rodent Species (Rodentia, Ctenomyidae)
Karger Publishers
2017
Ctenomys maulinus
Fish
Meiosis
Microdissection
Sex Chromosomes
Tuco-tucos
XY differentiation
2017-03-14 12:34:27
Dataset
https://karger.figshare.com/articles/dataset/Supplementary_Material_for_Homomorphic_Sex_Chromosomes_and_the_Intriguing_Y_Chromosome_of_Ctenomys_Rodent_Species_Rodentia_Ctenomyidae_/4750936
<p>Unlike the X chromosome, the mammalian Y chromosome undergoes
evolutionary decay resulting in small size. This sex chromosomal
heteromorphism, observed in most species of the fossorial rodent <i>Ctenomys</i>, contrasts with the medium-sized, homomorphic acrocentric sex chromosomes of closely related <i>C. maulinus </i>and <i>C. </i>sp.
To characterize the sequence composition of these chromosomes,
fluorescent banding, self-genomic in situ hybridization, and fluorescent
in situ hybridization with an X painting probe were performed on
mitotic and meiotic plates. High molecular homology between the sex
chromosomes was detected on mitotic material as well as on meiotic
plates immunodetected with anti-SYCP3 and anti-γH2AX. The Y chromosome
is euchromatic, poor in repetitive sequences and differs from the X by
the loss of a block of pericentromeric chromatin. Inferred from the
G-banding pattern, an inversion and the concomitant prevention of
recombination in a large asynaptic region seems to be crucial for
meiotic X chromosome inactivation. These peculiar findings together with
the homomorphism of <i>Ctenomys</i> sex chromosomes are discussed in
the light of the regular purge that counteracts Muller's ratchet and the
probable mechanisms accounting for their origin and molecular homology.</p>