Worm Breeder's Gazette 5(2): 30

These abstracts should not be cited in bibliographies. Material contained herein should be treated as personal communication and should be cited as such only with the consent of the author.

Ontogeny of Poly(A)+ RNA in C. elegans

R.M. Hecht, L.A. Gossett, W.R. Jeffery

We have examined the titer of poly(A) RNA in squashes prepared from 
oocytes and variously staged embryos of the nematode Caenorhabditis 
istol (N2) by In situ hybridization with a 
[3H]-poly(U) probe.  Control experiments demonstrated that this probe 
interacts specifically with poly(A) sequences and is capable of 
detecting poly(A) RNA.  Using this method and saturating 
concentrations of the probe, it was shown that isolated oocytes and 
embryos up to the 125-cell state exhibited substantial levels of poly(
A) RNA in their cytoplasms but almost no activity within their nuclei. 
Nuclear poly(A) RNA first appeared at the 90-cell stage and 
afterwards increased at a linear rate through the 550-cell stage.  The 
titer of total embryonic poly(A) RNA also increased at a linear rate 
up to larval hatching.  The results suggest that the major 
transcriptional effort for poly(A) RNA begins at the 90 to 125-cell 
stage of C.  elegans embryogenesis and that the poly(A) RNA present 
exclusively in the cytoplasm prior to this time is of maternal origin.