Journals of Gerontology Series A: Biological Sciences and Medical Sciences, Vol 50, Issue 5 B245-B253, Copyright © 1995 by The Gerontological Society of America
Identification genes that are differentially expressed during aging in Caenorhabditis elegans
TJ Fabian and TE Johnson
Department of Molecular, Cellular and Developmental Biology, University of Colorado at Boulder, USA.
We isolated cDNA clones of transcripts that undergo change in abundance
over the adult life span of the nematode Caenorhabditis elegans. Replicas
of a C. elegans cDNA library were probed with cDNA synthesized from poly(A)
+ RNA isolated from young or old nematodes. We identified clones
corresponding to nine distinct transcripts that decreased in abundance with
age, two distinct transcripts that increased slightly in abundance with
age, and one transcript that peaked in abundance during the early to middle
part of the adult life span. Six of the twelve transcripts were quantitated
as a function of age by means of a dot blot assay using total RNA isolated
at several ages from two strains that have wild-type life spans. All six
mRNAs showed similar age- dependent abundance patterns in these two
strains. Mutation of the age- 1 gene, which lengthens life span, did not
appear to alter these patterns. Nucleotide sequence analysis of clone
inserts revealed that three of the mRNAs that decreased in abundance with
age corresponded to previously identified C. elegans vitellogenin genes.
One transcript that showed a small increase in abundance with age appears
to encode translation factor EF1-alpha. The other five clones represent
novel nematode genes.
