http://www.loc.gov/mods/v3 http://www.loc.gov/standards/mods/v3/mods-3-2.xsd
Analysis of cyclin-dependent kinases as sensitive indicators of cellular proliferation in teleost embryos and larvae
xvi, 135 leaves : illustrations ; 28 cm.
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
"Major Subject: Wildlife and Fisheries Sciences".
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