Comparative transcriptomic analysis of the evolution and development of flower size in Saltugilia (Polemoniaceae)

BMC Genomics

Research Article

Jacob B. Landis¹  Douglas E. Soltis²  Pamela S. Soltis³ 

[1] Department of Biology, University of Florida, 32611, Gainesville, FL, USA;Florida Museum of Natural History, University of Florida, 32611, Gainesville, FL, USA;Department of Botany and Plant Sciences, University of California Riverside, 4412 Boyce Hall, 3401 Watkins Drive, 92521, Riverside, CA, USA;Department of Biology, University of Florida, 32611, Gainesville, FL, USA;Florida Museum of Natural History, University of Florida, 32611, Gainesville, FL, USA;Genetics Institute, University of Florida, 32610, Gainesville, FL, USA;Florida Museum of Natural History, University of Florida, 32611, Gainesville, FL, USA;Genetics Institute, University of Florida, 32610, Gainesville, FL, USA;

关键词: RNA-Seq;    Exon capture;    Flower Evo-Devo;    Corolla length;    Differential expression;   

DOI  :  10.1186/s12864-017-3868-2

 received in 2016-12-08, accepted in 2017-06-16,  发布年份 2017

来源: Springer

【 摘 要 】

BackgroundFlower size varies dramatically across angiosperms, representing innovations over the course of >130 million years of evolution and contributing substantially to relationships with pollinators. However, the genetic underpinning of flower size is not well understood. Saltugilia (Polemoniaceae) provides an excellent non-model system for extending the genetic study of flower size to interspecific differences that coincide with variation in pollinators.ResultsUsing targeted gene capture methods, we infer phylogenetic relationships among all members of Saltugilia to provide a framework for investigating the genetic control of flower size differences via RNA-Seq de novo assembly. Nuclear concatenation and species tree inference methods provide congruent topologies. The inferred evolutionary trajectory of flower size is from small flowers to larger flowers. We identified 4 to 10,368 transcripts that are differentially expressed during flower development, with many unigenes associated with cell wall modification and components of the auxin and gibberellin pathways.ConclusionsSaltugilia is an excellent model for investigating covarying floral and pollinator evolution. Four candidate genes from model systems (BIG BROTHER, BIG PETAL, GASA, and LONGIFOLIA) show differential expression during development of flowers in Saltugilia, and four other genes (FLOWERING-PROMOTING FACTOR 1, PECTINESTERASE, POLYGALACTURONASE, and SUCROSE SYNTHASE) fit into hypothesized organ size pathways. Together, these gene sets provide a strong foundation for future functional studies to determine their roles in specifying interspecific differences in flower size.

【 授权许可】

CC BY   
© The Author(s). 2017