Kinetochores and chromatin diminution in early embryos of Parascaris univalens.
نویسندگان
چکیده
منابع مشابه
Kinetochores and chromatin diminution in early embryos of Parascaris univalens
In Parascaris the mitotic chromosomes of gonial germline cells are holocentric and possess a continuous kinetochore along their entire length. By contrast, in meiotic cells, the centromeric activity is restricted to the heterochromatic tips where direct insertion of spindle microtubules into chromatin without any kinetochore plate is seen. In the presomatic cells of early embryos, which undergo...
متن کاملChromatin diminution is strictly correlated to somatic cell behavior in early development of the nematode Parascaris univalens.
We have studied the relationship between the occurrence of chromatin diminution and the developmental behavior of somatic blastomeres in early development of the nematode Parascaris univalens. A cytological and immunocytochemical analysis of chromatin diminution was performed in P. univalens embryos exposed to 'vegetalizing' (LiCl) and 'animalizing' (NaSCN) substances during early developmental...
متن کاملChromatin diminution leads to rapid evolutionary changes in the organization of the germ line genomes of the parasitic nematodes A. suum and P. univalens.
Chromatin diminution in the parasitic nematodes Ascaris suum and Parascaris univalens represents a rather complex molecular phenomenon that includes chromosomal breakage, DNA degradation and new telomere formation. At a given elimination site, DNA breakage and new telomere addition does not take place at a single chromosomal locus but at many different places within a several kilobase long chro...
متن کاملA centrosome-associated antibody from Drosophila melanogaster reveals a new microtubule-dependent structure in the equatorial zone of Parascaris univalens embryos.
The distribution of antigens to two antibodies (Bx63 and Rb188) that associate to Drosophila melanogaster centrosomes has been investigated in the nematode Parascaris. By western blot analysis both antibodies identify in Parascaris polypeptides of the same molecular mass as in Drosophila (Rb188 a 185 kDa antigen and Bx63 185 kDa and 66 kDa antigens). By immunocytochemistry we show that the cent...
متن کاملGenetic proof of chromatin diminution under mitotic agamospermy
The previously published data are examined on the base of the hypothesis about existence of differential polyteny of chromosomes and excess chromatin diminution during the first stages of embryogenesis. It has been concluded that available data provide the genetic proof that chromatin diminution is one of the mechanisms underlying the origin of polymorphism in sugar beet agamospermous progenies...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Journal of Cell Biology
سال: 1992
ISSN: 0021-9525,1540-8140
DOI: 10.1083/jcb.118.1.23