Insect sex chromosomes |
| |
Authors: | S R V Rao Paramjit Arora |
| |
Institution: | (1) Department of Zoology, University of Delhi, 110007 Delhi, India |
| |
Abstract: | A presumptive mechanism of X inactivation has been investigated by using tritiated uridine-induced chromosome aberrations to distinguish active from inactive X chromosome arms in the insect Gryllotalpa fossor. Previous work on therian mammals has shown that constitutive and facultative heterochromatin are less susceptible to breakage by 3H-Urd than euchromatin (active). The present study indicates that, irrespective of the presence of two X chromosomes in females, only one of these is affected as in males and that the total number of aberrations induced by 3H-Urd in both male and female Gryllotalpa is the same. This suggests that in the female only one arm of one X chromosome is active and that a facultative heterochromatinization of the homologous arm of the other X is operative coupled with the presence of constitutive heterochromatin in the second arm of both X chromosomes. |
| |
Keywords: | |
本文献已被 SpringerLink 等数据库收录! |
|