Analysis of cyclin-dependent kinases as sensitive indicators of cellular proliferation in teleost embryos and larvae /
Morphological, biochemical, and molecular studies of cellular
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| Format: | Thesis Book |
| Language: | English |
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[Place of publication not identified] :
[publisher not identified] ;
1995.
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| Online Access: | Link to OAKTrust copy http://proxy.library.tamu.edu/login?url=http://proquest.umi.com/pqdweb?did=742745921&sid=1&Fmt=2&clientId=2945&RQT=309&VName=PQD |
| Summary: | Morphological, biochemical, and molecular studies of cellular proliferation in developing teleost embryos and larvae were performed. Temperature-dependent embryonic developmental rates of geographically distinct populations of Fundulus heteroclitus were determined in the laboratory by morphological staging. Embryos from Massachusetts populations developed faster and hatched earlier than embryos of Florida populations at all temperatures examined, and had lower incipient lethal temperature limits. Results suggest intrinsic embryonic developmental rates between populations differ during cleavage stage and that this adaptation results in appropriate hatching during the spring tidal cycle. Analysis of pl3suc1-precipitated proteins from F. heteroclitus embryos, demonstrated proteins similar or identical to the cyclin-dependent kinase (cdk), p34cdc2, and cyclin B. Appropriately sized, pl3suc1-precipitated proteins crossreacted with antiPSTAIR and cyclin B antibodies, readily phosphorylated histone HI protein and peptide, and had oscillating activity relative to cleavage cell cycles consistent with identification as MPF. p34suc1-precipitated MPF did not contain phosphotyrosine over the first three cell cycles following fertilization and had a Km for ATP and histone HI peptide of 51.83 and 11.97 uM, respectively. A quantitative assay of cdk enzyme activity was developed and cdk kinetic parameters defined for Sciaenops ocellatus. Suc 1-precipitated cdks from S. ocellatus had a Km for ATP and histone H1 peptide of 97.34 and 13.65 JIM, respectively. Reaction conditions stabilized cdks and allowed linear incorporation of labeled phosphate into a histone H I peptide over a two hour period. Temperature and feeding level effects on cdk activity in developing S. ocellatus larvae were determined to examine an hypothesis that cdk activity may accurately reflect cellular proliferation in teleost embryos and larvae. Results of two growth experiments clearly demonstrated that in both experiments, tissues of rapidly growing larvae had significantly higher MPF activity and MPF larva-I than more slowly growing cohorts on 5 of 6 days analyzed. MPF activity larva-I had a large dynamic range, scaled with larval growth rates, and may reflect developmental-proliferative events. Results support analysis of cdk activity as a sensitive and cell cycle specific indicator of cellular proliferation in teleost embryos and larvae. |
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| Item Description: | Vita. "Major Subject: Wildlife and Fisheries Sciences". |
| Physical Description: | xvi, 135 leaves : illustrations ; 28 cm. Issued also on microfiche from University Microfilms Inc. |
| Bibliography: | Includes bibliographical references. |