Higher axial-resolution and sensitivity pachytene fluorescence in situ hybridization protocol in tetraploid cotton.
Fluorescence in situ hybridization (FISH) based on pachytene chromosomes has become an important cytogenetic tool to construct high axial-resolution and sensitivity cytogenetic maps. However, the application of this technique in cotton has lagged behind due to difficulties in chromosome preparation. To date, successful FISH based on cotton pachytene chromosomes has not been reported. In this study, the first protocol developed for pachytene chromosome preparation in tetraploid cotton is presented. This protocol yielded chromosome spreads suitable for large and small DNA probe FISH labeling. Two important parameters, axial-resolution and sensitivity, of FISH on mitotic metaphase and pachytene chromosomes were systematically analyzed. The results demonstrated that DNA targets separated by 0.6 cM and low-copy targets as small as 3-kb were resolved and detected, respectively, in pachytene FISH. The application of our FISH protocol will continue to improve and provide a point of departure for constructing an integrated high axial-resolution cytogenetic map in cotton.
Wang
Kai
K
National Key Laboratory of Crop Genetics and Germplasm Enhancement, Cotton Research Institute, Nanjing Agricultural University, Nanjing 210095, China.
Yang
Zaijie
Z
Shu
Changshen
C
Hu
Jing
J
Lin
Qiuyun
Q
Zhang
Wenpan
W
Guo
Wangzhen
W
Zhang
Tianzhen
T
D032461:Chromosomes, Plant; D018744:DNA, Plant; D003368:Gossypium / Q000166:cytology / Q000235:genetics*; D017404:In Situ Hybridization, Fluorescence / Q000379:methods*; D049471:Pachytene Stage / Q000235:genetics*; D011003:Ploidies
D018744:DNA, Plant