Plastome of the mycoheterotrophic eudicot Exacum paucisquama (Gentianaceae) exhibits extensive gene loss and a highly expanded inverted repeat region.

ABSTRACT: Mycoheterotrophic plants are highly specialized species able to acquire organic carbon from symbiotic fungi, with relaxed dependence on photosynthesis for carbon fixation. The relaxation of the functional constraint of photosynthesis and thereby the relaxed selective pressure on functional photosynthetic genes usually lead to substantial gene loss and a highly degraded plastid genome in heterotrophs. In this study, we sequenced and analyzed the plastome of the eudicot Exacum paucisquama, providing the first plastid genome of a mycoheterotroph in the family Gentianaceae to date. The E. paucisquama plastome was 44,028 bp in length, which is much smaller than the plastomes of autotrophic eudicots. Although the E. paucisquama plastome had a quadripartite structure, a disti

SUBMITTER: Li Z 

PROVIDER: S-EPMC7292021 | biostudies-literature | 2020

REPOSITORIES: biostudies-literature