TY  - JA
AU  - Carlson,W.R.
AU  - Roseman,R.R.
TI  - A new property of the maize B chromosome
SN  - 0016-6731
U1  - 92-103876 
PY  - 1992///
KW  - Biological development
KW  - Cell division
KW  - Cell structure
KW  - Gramineae
KW  - Nucleus
KW  - Plant genetics and breeding
KW  - NOT IN AGROVOC
KW  - Recombination
KW  - Zea
N1  - Peer-review: Yes - Open Access: Yes|http://science.thomsonreuters.com/cgi-bin/jrnlst/jlresults.cgi?PC=MASTER&ISSN=1943-2631; references US (DNAL 442.8 G28)
N2  - TB-9Sb is a translocation between the B chromosome and chromosome 9 in maize. Certain deletions of B chromatin from the translocation cause a sharp decrease in B-9 transmission compared to the rate for standard TB-9Sb. The deletions remove components of a B chromosome genetic system that serves to suppress meiotic loss in the female. At least two distinct B-chromosome regions suppress meiotic loss: one on the B-9 and one on 9-B. The system operates by stabilizing univalent B-type chromosomes. It allows the univalents to migrate to one pole in meiosis, despite the absence of a pairing partner. The findings reported here are the first evidence for genetic control of meiotic loss by a B chromosome. However, it is proposed that the practice of suppressing meiotic loss is common to the B chromosomes of all species. The need to suppress meiotic loss results from the fact that B chromosomes are frequently unpaired in meiosis and subject to very high frequencies of loss. B chromosomes may utilize one or more of the following methods to suppress meiotic loss: (a) regular migration of univalent B's to one pole in meiosis, (b) enhanced recombination between B chromosomes and (c) mitotic nondisjunction
T2  - Genetics
ER  -