Analysis of wheat microspore embryogenesis induction by transcriptome and small RNA sequencing using the highly responsive cultivar “Svilena”

Abstract

BackgroundMicrospore embryogenesis describes a stress-induced reprogramming of immature male plant gametophytes to develop into embryo-like structures, which can be regenerated into doubled haploid plants after whole genome reduplication. This mechanism is of high interest for both research as well as plant breeding. The objective of this study was to characterize transcriptional changes and regulatory relationships in early stages of cold stress-induced wheat microspore embryogenesis by transcriptome and small RNA sequencing using a highly responsive cultivar.ResultsTranscriptome and small RNA sequencing was performed in a staged time-course to analyze wheat microspore embryogenesis induction. The analyzed stages were freshly harvested, untreated uninucleate microspores and the two following stages from in vitro anther culture: directly after induction by cold-stress treatment and microspores undergoing the first nuclear divisions. A de novo transcriptome assembly resulted in 29,388 contigs distributing to 20,224 putative transcripts of which 9,305 are not covered by public wheat cDNAs. Differentially expressed transcripts and small RNAs were identified for the stage transitions highlighting various processes as well as specific genes to be involved in microspore embryogenesis induction.ConclusionThis study establishes a comprehensive functional genomics resource for wheat microspore embryogenesis induction and initial understanding of molecular mechanisms involved. A large set of putative transcripts presumably specific for microspore embryogenesis induction as well as contributing processes and specific genes were identified. The results allow for a first insight in regulatory roles of small RNAs in the reprogramming of microspores towards an embryogenic cell fate.Electronic supplementary materialThe online version of this article (doi:10.1186/s12870-016-0782-8) contains supplementary material, which is available to authorized users.

Transcriptomics analyses reveal the molecular roadmap and long non‐coding RNA landscape of sperm cell lineage development

“…Retaining the somatic molecular features suggests that cell fate transition is not completed at the microspore stage. Together with the cytological observation that the microspore can be dedifferentiated and generates a somatic embryo in vitro (Segui-Simarro and Nuez, 2007;Daghma et al, 2014;Seifert et al, 2016), these findings indicate somatic fate and a potential pluripotent state of the microspore at the molecular level.…”

“…The microspore retains the molecular features of somatic cells A microspore is cytologically considered a type of pluripotent cell that develops into an embryo-like structure upon stress or hormone induction (Honys and Twell, 2004;Segui-Simarro and Nuez, 2007;Daghma et al, 2014;Seifert et al, 2016); however, molecular evidence supporting this concept is still limited. Principal component analysis (PCA) and correlation matrix analysis showed that the mRNome of the microspore is closer to that of callus (r = 0.71), leaf (r = 0.65) and pistil (r = 0.72) than that of the GC (r = 0.46), SCs (r = 0.35) and MPG (r = 0.40) (Figures 2a and S2a, Table S5).…”

Androgenic response of wheat genotypes resistant to fusariosis

“…agropec. bras., Brasília, v.53, n.5, p.575-582, May 2018 DOI: 10.1590/S0100-204X2018000500006 like feature, which has been previously reported as a representative morphology of totipotent cells (Seifert et al, 2016). Immediately after this phase, the first divisions were observed, although, in most genotypes, it occurred 20 days post-incubation.…”

Haploid and Doubled Haploid Techniques in Perennial Ryegrass (Lolium perenne L.) to Advance Research and Breeding

“…For example in Brassicas, microspore mutation studies have enabled modifications of disease resistance, cold tolerance, and fatty acid composition [43]. Additionally, in vitro microspore culture systems have allowed for detailed study of embryogenesis, early cell fate decisions, embryogenesis, and totipotency [44][45][46]. All of these applications of haploid and DH techniques, as well as many others not mentioned here, could confer the same benefits to perennial ryegrass breeding and research as they have done, and currently do, in species for which effective and efficient DH induction protocols are available [14].…”