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bioRxiv · 10.1101/2023.08.29.555143

Allelic promoter variation causes a switch in reproductive tissue expression in an Arabidopsis exonuclease gene

Honari, M.·Ernest, J.·Sharbel, T.
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Abstract

Among candidate genes underlying the control components of apomixis, APOLLO is known for its strong linkage to apomeiosis in the genus Boechera. The gene has "apo-alleles", which are characterized by a set of linked apomixis-specific polymorphisms, and "sex-alleles". All apomictic{square}Boechera genotypes are heterozygous for the apo/sex-alleles, while all sexual genotypes are homozygous for sex-alleles. In this study, native and synthetic APOLLO promoters were characterized by detecting the expression level of the {beta}-glucuronidase (GUS) gene in Arabidopsis. Comparing various flower developmental stages in transgenic lines containing different constructs with 2 kb native transgenic lines revealed that changes to the APOLLO promoter causes shifts in tissue- and developmental-stage specificity of GUS expression. Importantly, several apomixis-specific polymorphisms in the 5UTR change the timing and location of GUS activity from somatic to reproductive tissues. These synthetic data simulate a plausible evolutionary process whereby apomixis-specific gene activity can be achieved.

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Honari, M., Ernest, J., Sharbel, T.. 2023-08-31. Allelic promoter variation causes a switch in reproductive tissue expression in an Arabidopsis exonuclease gene. https://doi.org/10.1101/2023.08.29.555143

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