INVESTIGADORES
PIGOZZI Maria Ines
artículos
Título:
Equal frequencies of recombination nodules in both sexes of the pigeon suggest a basic difference with eutherian mammals.
Autor/es:
PIGOZZI MI; SOLARI AJ
Revista:
Genome
Editorial:
CNR PRESS
Referencias:
Año: 1999 vol. 42 p. 315 - 321
ISSN:
0831-2796
Resumen:
The total number of recombination nodules (RNs) in the autosomal
synaptonemal complexes (SCs) is statistically equivalent in oocytes and
spermatocytes from the domestic pigeon Columba livia. The distribution
on RNs along the three longest autosomes is also equivalent in oocytes
and spermatocytes. The numbers of RNs show a linear relationship when
plotted against SC length both in oocytes and spermatocytes. On the
other hand, the ZW pair shows a single and strictly localized RN near
the synaptic termini, but the ZZ pair shows unrestricted location of RNs
(average 3.8). The ZW and ZZ pairs of the pigeon are euchromatic and do
not show specific chromatin packing at pachytene in either sex. The
lack of sex-specific differences in the number and location of RNs in
the autosomal bivalents of C. livia and previous data on the chicken,
suggest that the regulation of crossing-over is basically different in
birds and mammals.
