Belén Méndez-Vigo, Noelia Arteaga, Alba Murillo-Sánchez, Sonia Alba, Carlos Alonso-Blanco
{"title":"The bHLH transcription factor gene EGL3 accounts for the natural diversity in Arabidopsis fruit trichome pattern and morphology","authors":"Belén Méndez-Vigo, Noelia Arteaga, Alba Murillo-Sánchez, Sonia Alba, Carlos Alonso-Blanco","doi":"10.1093/plphys/kiae673","DOIUrl":null,"url":null,"abstract":"The number and distribution of trichomes, i.e., the trichome pattern, in different plant organs shows a conspicuous inter- and intraspecific diversity across Angiosperms that is presumably involved in adaptation to numerous environmental factors. The genetic and molecular mechanisms accounting for the evolution of trichome patterns have just begun to be elucidated. In this study, we aimed to identify and characterize MALAMBRUNO 1 (MAU1), a locus affecting trichome number in the fruits of Arabidopsis (Arabidopsis thaliana) natural populations. To this end, we developed introgression lines (ILs) from the hairy fruit accession Don-0 in the genetic background of the Ler strain with glabrous fruits. Genetic analyses of ILs showed that MAU1 affects fruit trichome patterns through synergistic epistasis with the MYB genes TRICHOMELESS1 (TCL1), GLABRA1 (GL1), and TRIPTYCHON (TRY). In addition, fine mapping and characterization of transgenic lines demonstrated that MAU1 is the bHLH transcription factor gene EGL3, for which Don-0 carries a gain-of-function semidominant allele. Gene expression analyses did not detect differences between EGL3 alleles, thus supporting that a structural missense mutation is the causal nucleotide polymorphism of Don-0. Further phylogenetic analyses of EGL3 showed that most Arabidopsis populations with hairy fruits belong to three haplogroups, suggesting that additional EGL3 natural alleles account for fruit trichome development. Finally, the characterization of EGL3 pleiotropy indicates that Don-0 hyperfunction also increases stem trichome branching. We conclude that EGL3 interactions in the core gene regulatory network of trichome development explain the Arabidopsis natural diversity for fruit trichome pattern and morphology.","PeriodicalId":20101,"journal":{"name":"Plant Physiology","volume":"61 1","pages":""},"PeriodicalIF":6.5000,"publicationDate":"2024-12-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Plant Physiology","FirstCategoryId":"99","ListUrlMain":"https://doi.org/10.1093/plphys/kiae673","RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"PLANT SCIENCES","Score":null,"Total":0}
引用次数: 0
Abstract
The number and distribution of trichomes, i.e., the trichome pattern, in different plant organs shows a conspicuous inter- and intraspecific diversity across Angiosperms that is presumably involved in adaptation to numerous environmental factors. The genetic and molecular mechanisms accounting for the evolution of trichome patterns have just begun to be elucidated. In this study, we aimed to identify and characterize MALAMBRUNO 1 (MAU1), a locus affecting trichome number in the fruits of Arabidopsis (Arabidopsis thaliana) natural populations. To this end, we developed introgression lines (ILs) from the hairy fruit accession Don-0 in the genetic background of the Ler strain with glabrous fruits. Genetic analyses of ILs showed that MAU1 affects fruit trichome patterns through synergistic epistasis with the MYB genes TRICHOMELESS1 (TCL1), GLABRA1 (GL1), and TRIPTYCHON (TRY). In addition, fine mapping and characterization of transgenic lines demonstrated that MAU1 is the bHLH transcription factor gene EGL3, for which Don-0 carries a gain-of-function semidominant allele. Gene expression analyses did not detect differences between EGL3 alleles, thus supporting that a structural missense mutation is the causal nucleotide polymorphism of Don-0. Further phylogenetic analyses of EGL3 showed that most Arabidopsis populations with hairy fruits belong to three haplogroups, suggesting that additional EGL3 natural alleles account for fruit trichome development. Finally, the characterization of EGL3 pleiotropy indicates that Don-0 hyperfunction also increases stem trichome branching. We conclude that EGL3 interactions in the core gene regulatory network of trichome development explain the Arabidopsis natural diversity for fruit trichome pattern and morphology.
期刊介绍:
Plant Physiology® is a distinguished and highly respected journal with a rich history dating back to its establishment in 1926. It stands as a leading international publication in the field of plant biology, covering a comprehensive range of topics from the molecular and structural aspects of plant life to systems biology and ecophysiology. Recognized as the most highly cited journal in plant sciences, Plant Physiology® is a testament to its commitment to excellence and the dissemination of groundbreaking research.
As the official publication of the American Society of Plant Biologists, Plant Physiology® upholds rigorous peer-review standards, ensuring that the scientific community receives the highest quality research. The journal releases 12 issues annually, providing a steady stream of new findings and insights to its readership.