Expression of replication-dependent histone genes in avian spermatids involves an alternate pathway of mRNA 3'-end formation.
AUTOR(ES)
Challoner, P B
RESUMO
In somatic cells the expression of replication-dependent histone genes is coupled to the S phase of the cell cycle. However, we have found a number of novel H2a, H2b, and H3 poly(A)+ RNA species in avian haploid round spermatids. The spermatid-specific H2a and H2b 0.8-kilobase RNAs are transcribed from a subset of the replication-dependent H2a and H2b gene families. Two cDNAs derived from the spermatid-specific H2b transcripts were isolated and sequenced. The structures of these cDNAs reveal that the spermatid-specific RNAs are identical to the 0.5-kilobase poly(A)- H2b mRNAs expressed in proliferating somatic cells, except for the addition of poly(A) at the 3' ends. The site of poly(A) addition in the spermatid-specific RNAs is located 26 to 28 nucleotides 3' of the poly(A)- H2b mRNA terminus. Thus, the hairpin structures and purine-rich elements required for the U7 small nuclear ribonucleoprotein-mediated cleavage reaction that generates the 3' ends of poly(A)- H2b mRNAs are not utilized in spermatids and are retained in the poly(A)+ H2b RNAs.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=362679Documentos Relacionados
- CDK9 directs H2B monoubiquitination and controls replication-dependent histone mRNA 3′-end processing
- An alternative pathway of histone mRNA 3' end formation in mouse round spermatids.
- DNA Replication-Dependent Histone H2A mRNA Expression in Pea Root Tips.
- REF2 encodes an RNA-binding protein directly involved in yeast mRNA 3'-end formation.
- DNA-Directed Expression of an Animal Virus RNA for Replication-Dependent Colony Formation in Saccharomyces cerevisiae