Polymorphism pattern at a miniature inverted‐repeat transposable element locus downstream of the domestication gene Teosinte‐branched1 in wild and domesticated pearl millet. Issue 2 (3rd December 2012)

• Record Type: Journal Article
• Authors: Dussert, Y.; Remigereau, M.‐S.; Fontaine, M. C.; Snirc, A.; Lakis, G.; Stoeckel, S.; Langin, T.; Sarr, A.; Robert, T.
• Is Part Of: Molecular ecology. Volume 22:Issue 2(2013)
• Page Start: 327
• Page End: 340
• Publication Date: 2012-12-03
• Subjects: Molecular ecology -- Periodicals; Molecular population biology -- Periodicals; 576
• DOI: 10.1111/mec.12139
• Languages: English
• ISSNs: 0962-1083

Abstract

<abstract abstract-type="main" id="mec12139-abs-0001"> <title>Abstract</title> <p>Unravelling the mechanisms involved in adaptation to understand plant morphological evolution is a challenging goal. For crop species, identification of molecular causal polymorphisms involved in domestication traits is central to this issue. Pearl millet, a domesticated grass mostly found in semi‐arid areas of Africa and India, is an interesting model to address this topic: the domesticated form shares common derived phenotypes with some other cereals such as a decreased ability to develop basal and axillary branches in comparison with the wild phenotype. Two recent studies have shown that the orthologue of the maize gene <italic>Teosinte‐Branched1</italic> in pearl millet (<italic>PgTb1</italic>) was probably involved in branching evolution during domestication and that a miniature inverted‐repeat transposable element (MITE) of the <italic>Tuareg</italic> family was inserted in the 3′ untranslated region of <italic>PgTb1</italic>. For a set of 35 wild and domesticated populations, we compared the polymorphism patterns at this MITE and at microsatellite loci. The <italic>Tuareg</italic> insertion was nearly absent in the wild populations, whereas a strong longitudinal frequency cline was observed in the domesticated populations. The geographical pattern revealed by neutral microsatellite loci clearly demonstrated that isolation by distance does not account for the existence of this cline. However, comparison of population differentiation at the microsatellite and the MITE loci and analyses of the nucleotide polymorphism pattern in the downstream region of <italic>PgTb1</italic> did not show evidence that the cline at the MITE locus has been shaped by selection, suggesting the implication of a neutral process. Alternative hypotheses are discussed.</p> </abstract>