Skip to main content
Log in

The Evolution of Single-Copy Drosophila Nuclear 4f-rnp Genes: Spliceosomal Intron Losses Create Polymorphic Alleles

  • Published:
Journal of Molecular Evolution Aims and scope Submit manuscript

This study provides the first report in which spliceosomal intron losses within a single-copy gene create functional polymorphic alleles in a population. 4f-rnp has previously been shown to be a nuclear gene that is localized on the X chromosome in D. melanogaster and to have eight short spliceosomal introns. An insect species survey was done via polymerase chain reaction (PCR) amplification and sequencing of a 1028-bp gene fragment spanning introns 4–8, which are located in the 3? half of the gene. The results show that 4f-rnp and (thus far) introns 7 and 8 are at least as old as order Odonata (dragonflies), an early-diverging insect line. Unexpectedly, several species within the dipteran family Drosophilidae were found to contain two differently sized 4f-rnp gene sequence variants, owing to precise in-frame intron losses. Results of single-male D. melanogaster PCR analyses show that the two gene size variants are allelic and that the intron loss mechanism appears to be biased toward the 3? end of the gene. A stable potential stem–loop has been identified in D. melanogaster, predicted to fold the 4f-rnp mRNA 3? terminus into a natural primer for subsequent reverse transcription into cDNA. When results are displayed in a phylogenetic context, multiple independent intron loss events are identified. These observations support a model in which frequently occurring cDNAs have led to numerous independent intron losses via homologous recombination/gene conversion during 4f-rnp gene evolution. The results provide insights into the evolution of intron loss and may lead to improved understanding of the dynamics of this process in natural populations.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Similar content being viewed by others

Author information

Authors and Affiliations

Authors

Rights and permissions

Reprints and permissions

About this article

Cite this article

Feiber, A., Rangarajan, J. & Vaughn, J. The Evolution of Single-Copy Drosophila Nuclear 4f-rnp Genes: Spliceosomal Intron Losses Create Polymorphic Alleles . J Mol Evol 55, 401–413 (2002). https://doi.org/10.1007/s00239-002-2336-y

Download citation

  • Received:

  • Accepted:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s00239-002-2336-y

Keywords

Navigation