Structure and variation of the Nucleolus Organizer Region in turtles |
| |
Authors: | J W Bickham D S Rogers |
| |
Institution: | (1) Department of Wildlife and Fisheries Sciences, Texas A& M University, 77843 College Station, TX, USA;(2) Museum of Vertebrate Zoology, University of California, 94720 Berkeley, CA, USA;(3) Present address: Department of Biology, Texas A& M University, 77843 College Station, TX, USA |
| |
Abstract: | Differential staining techniques were used to study the structure and variation of the NORs of 27 species of cryptodiran turtles.
No species or individuals had more than a single pair of NORs. Extensive variation in NOR structure and chromosomal location
was found among higher taxa and individual variation in NOR size was common. Thirty eight percent of all individuals studied
were heterozygous for the size of the NOR. However, interspecific variation in chromosomal location and structure of the NOR
within major taxa was relatively rare. It is concluded that ( I ) the pattern of variation of NORs is consistent with patterns
of chromosomal evolution in turtles; (2) Turtles have only a single pair of NORs whereas other animals, such as some mammals,
possess numerous NORs; (3) The heterochromatin associated with the NOR is involved in the structure of the nucleolus. |
| |
Keywords: | |
本文献已被 SpringerLink 等数据库收录! |
|