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271.
Hämäläinen Anni Immonen Elina Tarka Maja Schuett Wiebke 《Behavioral ecology and sociobiology》2018,72(3):1-13
Behavioral Ecology and Sociobiology - The success of social insect colonies is dependent upon efficient and dynamic allocation of resources to alternate queen and worker castes. The developmental... 相似文献
272.
Levels of total RNA, total DNA, 18S ribosomal RNA (rRNA), poly(A) messenger RNA (mRNA), and two mRNAs coding for abundant
myofibrillar proteins were estimated in laboratory-reared Atlantic cod larvae (Gadusmorhua Linnaeus) under conditions of feeding and starvation. DNA probes specific for cod 18S rRNA, β-actin mRNA and myosin heavy
chain mRNA were developed. In two experiments on newly hatched larvae in fed and starved treatments, changes in 18S rRNA and
mRNA were similar to changes in total RNA during the first weeks after hatching. RNA levels in fed and starved larvae in both
experiments were stable, or increased, over the first 3 d after hatching, and then decreased to minima at 9 d. RNA levels
increased after 9 d, with the degree and timing of the increase varying among the individual classes of RNA. Complete mortality
of starved larvae in both experiments was observed shortly after 11 d, corresponding to exhaustion of endogenous yolk reserves.
Total RNA content, RNA/DNA ratio, 18S rRNA levels, total mRNA pool, and actin and myosin heavy chain mRNA levels showed significant
differences in fed and starved first-feeding larvae after yolk exhaustion. In another experiment with 3- to 4-week-old cod
larvae, 18S rRNA levels were significantly lower in starved versus fed larvae after 3 d. Total RNA responded to feeding and
starvation within a similar time as 18S rRNA and the mRNAs examined. Analysis of bulk nucleic acids using fluorometric dyes
was simpler and faster than analysis of individual RNAs using hybridization probes, and provides valuable information on recent
growth and condition of individual larvae. However, analysis of specific RNAs can provide information on expression of the
corresponding genes and reveal the changes underlying trends seen in bulk RNA.
Received: 9 February 1996 / Accepted: 7 June 1999 相似文献