Construction and characterization of deep coverage BAC libraries for two model crops - tomato and rice, and initiation of a chromosome walk to jointless-2 in tomato /
The development of gene discovery strategies to identify agriculturally useful single and quantitative genes has evolved from single gene isolation to whole genome approaches. An essential element in all of generics based approaches from map-based cloning to genome sequencing is large insert genomic...
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| Format: | Thesis Book |
| Language: | English |
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[Place of publication not identified] :
[publisher not identified] ;
1999.
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| Online Access: | http://proxy.library.tamu.edu/login?url=http://proquest.umi.com/pqdweb?did=733667951&sid=1&Fmt=2&clientId=2945&RQT=309&VName=PQD |
| Summary: | The development of gene discovery strategies to identify agriculturally useful single and quantitative genes has evolved from single gene isolation to whole genome approaches. An essential element in all of generics based approaches from map-based cloning to genome sequencing is large insert genomic libraries. Here, the construction and characterization of BAC libraries for the model plants tomato and rice and the use of the tomato library to initiate map-based cloning of jointless-2 are presented. The tomato BAC library contains 129,024 clones with an average insert size of 117.5 kb covering 15.4 haploid genome equivalents. The library was screened with 19 tomato RFLP markers and at least 1 clone was identified for each marker. The feasibility of establishing a sequence tag connector (STC) framework to sequence the tomato genome using the BAC library was determined by sequencing 745 BACS from both ends. The end sequences were compared with all non-redundant databases and demonstrated that sequencing every end in the entire library will provide a STC every 3.64 kb across the genome and reveal the partial sequences of an estimated 68,000 genes. The rice library contains 36,864 clones with an average insert size of 128.5 kb, harboring 10.4 genome equivalents, which is the most comprehensive rice library to date. The characterization of library, in terms of blue, non-recombinant content, chloroplast content and other contaminants, suggests its usefulness for generics-based applications. The j-2 gene is agronomically valuable for the mechanized harvesting of processing tomatoes. J-2 isolation will help lead to a better understanding of abscission zone structure development in plants. Using the jointless-2 mutant, a RAPD marker tightly linked j-2 was identified and j-2 was mapped on chromosome 12 instead of chromosome 11 as previously published. J-2 is flanked by RPD14O, 0.7 cM on one side and TG618, 2.3 cM on the opposite side. Analysis of an expanded 172 population of 5,000 plants confirmed that RPD14O was tightly linked j-2. Screening the tomato BAC library with RPD14O resulted in a 300 kb cortig, demonstrating that the tomato BAC library could be used to begin to walk to j-2. |
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| Item Description: | Vita. "Major Subject: Plant Physiology". |
| Physical Description: | x, 180 leaves : illustrations ; 28 cm. Issued also on microfiche from University Microfilm Inc. |
| Bibliography: | Includes bibliographical references (leaves 127-156). |