Evolution of the scrambled germline gene encoding α-telomere binding protein in three hypotrichous ciliates

Jason D. Prescott, Michelle L. DuBois, David M. Prescott

Research output: Contribution to journalArticle

Abstract

The micronuclear genes encoding α-telomere-binding protein (αTP) in Oxytricha trifallax and Stylonychia mytilus contain multiple internal eliminated segments, or IESs, that divide the gene into multiple parts called macronuclear destined segments, or MDSs. The MDSs have become disordered, or scrambled, during evolution. The scrambled structures of the αTP genes in Oxytricha trifallax and S. mytilus have been compared with the previously published scrambled structure of the αTP gene in O. nova. The scrambled patterns of the αTP gene in the three species are similar but show significant differences. The micronuclear genes in O. nova and S. mytilus consist of 13 IESs and 14 MDSs, but the gene in O. trifallax is divided into three additional MDSs by the presence of three additional IESs, believed to have been inserted into the O. trifallax αTP gene after divergence of O. trifallax from the other two species. Corresponding IESs among the three species have shifted along the DNA during evolution, presumably by a mutational mechanism that changes the short repeat sequences that flank IESs. The IESs also have changed markedly in length by insertion and/or deletion of nucleotides. Comparison of the putative αTP amino acid sequences in the three species reveals three conserved and three non-conserved domains. The 5' nontranslated regions of the gene-sized molecules encoding αTP contain several conserved segments, and the 3' nontranscribed trailer contains one conserved segment.

Original languageEnglish (US)
Pages (from-to)293-303
Number of pages11
JournalChromosoma
Volume107
Issue number5
DOIs
StatePublished - Dec 16 1998
Externally publishedYes

ASJC Scopus subject areas

  • Genetics
  • Genetics(clinical)

Fingerprint Dive into the research topics of 'Evolution of the scrambled germline gene encoding α-telomere binding protein in three hypotrichous ciliates'. Together they form a unique fingerprint.

  • Cite this