Construction and characterization of a partial bacterial artificial chromosome (BAC) library and the use of BACs for physical mapping in plants using fluorescent in situ hybridization (FISH) /
A partial cotton bacterial artificial chromosome (BAC)
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| Format: | Thesis Book |
| Language: | English |
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[Place of publication not identified] :
[publisher not identified] ;
1997.
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| Subjects: | |
| Online Access: | http://proxy.library.tamu.edu/login?url=http://proquest.umi.com/pqdweb?did=736584801&sid=1&Fmt=2&clientId=2945&RQT=309&VName=PQD |
| Summary: | A partial cotton bacterial artificial chromosome (BAC) library consisting of 1,824 clones with an average insert size of 75 kb was constructed to aid in map-based cloning and physical mapping. BAC clones were screened with both chloroplast and Gossypium. hirsutum [L.] total genomic DNA and results indicate this library contains less than 3% cloned chloroplast DNA sequences and approximately 19% of the clones contain unique DNA sequences. Large unique BACs were used for fluorescent in situ hybridization (FISH) in several Gossypium species demonstrating that BACs can be used effectively for physical mapping. Some BACs however, were shown to consist largely of unique sequences with some repetitive DNA sequences interspersed within. These clones were still useful for FISH mapping although hybridization of repetitive DNA sequences needed to be suppressed. A technique to isolate Cot-1 DNA from plants was developed. Cot-1 DNA demonstrated the effective suppression of hybridization of repetitive DNA sequences in FISH mapping, and its usefulness as a probe in detecting repetitive DNA both in situ and ex situ. Since BAC FISH is an effective means of physical mapping, and members of the Gramineae contain highly conserved genetic regions, liguleless (Ig-1) associated RFLP markers from rice were used to screen the sorghum BAC library and selected BACs were used to physically map the liguleless linkage region in Sorghum bicolor L. [Moench]. Physical mapping in S. bicolor determined that the liguleless linkage group is basically conserved as in rice, although one marker which is distal in rice is more medial in sorghum and another marker which is found within the linkage group in rice is on a different chromosome in sorghum. A centromere subgenome-specific BAC was subcloned producing a clone containing a 1,096 bp insert that when FISHed hybridized intensely to the centromeres of 10 chromosomes of sorghum, with minor hybridization to the remaining chromosomes, indicating that Sorghum bicolor is a tetraploid. Sequence analysis suggests the sequence is an ancient retrotransposon while Southern hybridization determined the sequence is present in 3.6% of the BAC library and in approximately 100 - 150 copies per genome. |
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| Item Description: | Vita. "Major Subject: Genetics". |
| Physical Description: | xii, 134 leaves : illustrations ; 28 cm. Issued also on microfiche from University Microfilms Inc. |
| Bibliography: | Includes bibliographical references: pages 111-132. |