The transcription factor MtSERF1 of the ERF subfamily identified by transcriptional profiling is required for somatic embryogenesis induced by auxin plus cytokinin in Medicago truncatula.
Transcriptional profiling of embryogenic callus produced from Medicago truncatula mesophyll protoplasts indicated up-regulation of ethylene biosynthesis and ethylene response genes. Using inhibitors of ethylene biosynthesis and perception, it was shown that ethylene was necessary for somatic embryogenesis (SE) in this model legume. We chose several genes involved in ethylene biosynthesis and response for subsequent molecular analyses. One of these genes is a gene encoding a transcription factor that belongs to the AP2/ERF superfamily and ERF subfamily of transcription factors. We demonstrate that this gene, designated M. truncatula SOMATIC EMBRYO RELATED FACTOR1 (MtSERF1), is induced by ethylene and is expressed in embryogenic calli. MtSERF1 is strongly expressed in the globular somatic embryo and there is high expression in a small group of cells in the developing shoot meristem of the heart-stage embryo. RNA interference knockdown of this gene causes strong inhibition of SE. We also provide evidence that MtSERF1 is expressed in zygotic embryos. MtSERF1 appears to be essential for SE and may enable a connection between stress and development.
Mantiri
Feky R
FR
Australian Research Council Centre of Excellence for Integrative Legume Research, School of Environmental and Life Sciences, University of Newcastle, Callaghan, New South Wales 2308, Australia.
Kurdyukov
Sergey
S
Lohar
Dasharath P
DP
Sharopova
Natalya
N
Saeed
Nasir A
NA
Wang
Xin-Ding
XD
Vandenbosch
Kathryn A
KA
Rose
Ray J
RJ
D000595:Amino Acid Sequence; D001483:Base Sequence; D003583:Cytokinins / Q000378:metabolism*; D017931:DNA Primers; D018744:DNA, Plant; D020869:Gene Expression Profiling; D017343:Genes, Plant; D017403:In Situ Hybridization; D007210:Indoleacetic Acids / Q000378:metabolism*; D029902:Medicago / Q000235:genetics / Q000378:metabolism*; D008969:Molecular Sequence Data; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012639:Seeds / Q000254:growth & development*; D017386:Sequence Homology, Amino Acid; D014157:Transcription Factors / Q000737:chemistry / Q000235:genetics / Q000502:physiology*
D003583:Cytokinins; D017931:DNA Primers; D018744:DNA, Plant; D007210:Indoleacetic Acids; D014157:Transcription Factors