Haplotype-resolved genome of Forsythia suspensa reveals the reticulate evolution in Oleaceae and a novel gene cluster regulating stamen development.

Authors

Quanling Zhang, Ezi Zhao, Xiaomin Fu, Andong Zhu, Fan Zhang, Chen Fang, Hongxiu Liu, Xinxin Luan, Jianhua Wang, Guiqi Bi, Jianbin Yan, Xinsheng Fang

Published in

Plant physiology. Aug 24, 2026. Epub Aug 24, 2026.

Abstract

The olive family (Oleaceae) comprises numerous species of economic, horticultural, and medicinal importance. Despite its significance, the evolutionary history of this complex family remains enigmatic. Here, we generated a high-quality haplotype-resolved genome of Forsythia suspensa, a distylous species that occupies a key phylogenetic position in Oleaceae. The two haplotypes exhibit significant allelic divergence with potential allele-specific regulation. We reconstructed the polyploidization history of Oleaceae by confirming and precisely dating a shared whole-genome triplication (WGT) and an independent whole-genome duplication (WGD) event. We revealed a complex reticulate evolution that gave rise to the tribe Oleeae: an initial hybridization between Forsythieae (♂) and Jasmineae (♀), a subsequent backcrossing event, and a final WGD. We identified a novel tandemly duplicated pectin methylesterase inhibitor (PMEI) gene cluster that regulates filament length and pollen size via restricting cell elongation in the long-styled morph. Dosage augmentation via stepwise cluster formation (0.99-3.83 Mya) may contribute to maintaining stamen traits of the long-styled morph. These FsPMEIs are co-expressed with many cell wall-related genes, suggesting a functional link in cell wall modification. Our study reveals the reticulate evolution in Oleaceae and a novel gene cluster controlling stamen development in F. suspensa, provides valuable haplotype-resolved genomic resources for heterostylous species, offering novel framework and molecular pathways to understand plant adaptive evolution.

PMID:
42633801
Bibliographic data and abstract were imported from PubMed on 24 Aug 2026.

Read full publication at:
Please sign in to see all details.

Stats

1-terrible, 9-excellent. How would you rate this publication? Sign in in to submit your rating.

Post a comment

You need to be signed in to post comments. You can sign in here.

Comments

There are no comments yet.