TY - JOUR
T1 - Transcriptional profiling of the AFL subfamily of B3-type transcription factors during the in vitro induction of somatic embryogenesis in the model legume Medicago truncatula
AU - Barreto, Horllys Gomes
AU - Ságio, Solange Aparecida
AU - Chalfun-Júnior, Antonio
AU - Fevereiro, Pedro
AU - Benedito, Vagner Augusto
PY - 2019/11/1
Y1 - 2019/11/1
N2 - In many legume species, somatic embryogenesis is a limiting step of in vitro regeneration, with profound implications to genetic engineering and plant breeding. In Arabidopsis thaliana, the small AFL subfamily of B3-type transcriptional factors is composed by LEC2 (LEAFY COTYLEDON 2), FUSCA (FUSCA3), and ABI3 (ABSCISIC ACID INSENSITIVE 3), which are directly involved in both zygotic and somatic embryogenesis. This study aimed to identify and analyze the expression profile of AFL subfamily genes during in vitro induction of the somatic embryogenesis in the model legume Medicago using near-isogenic genotypes contrasting for their capability of regenerating in vitro. Three AFL genes were identified in the Medicago truncatula genome: MtLEC2, MtFUSCA3 and MtABI3. RT-qPCR was used to compare the expression of these genes during the induction of somatic embryogenesis in the embryogenic genotype M9-10a and the non-embryogenic genotype M9. The AFL genes identified were highly expressed 10 days after introducing leaflet explants in vitro in the embryogenic genotype (M9-10a), whereas absence or low expression was observed in explants of the non-embryogenic genotype (M9). During zygotic embryogenesis, the Medicago Gene Atlas revealed that expression of MtFUSCA3 and MtABI3 occurred specifically during seed development, starting at 10 days after pollination. This study allowed for the identification and transcriptional characterization of MtLEC2, MtFUSCA3, and MtABI3. The expression pattern of these genes in the M9-10a genotype suggests they are involved in the Medicago truncatula somatic embryogenesis. The transcriptional profile of AFL transcription factors highlights the evolutionary conservation of this developmental pathway between the Arabidopsis and Medicago lineages and opens avenues to improve the efficiency of in vitro embryogenesis in legume crops.
AB - In many legume species, somatic embryogenesis is a limiting step of in vitro regeneration, with profound implications to genetic engineering and plant breeding. In Arabidopsis thaliana, the small AFL subfamily of B3-type transcriptional factors is composed by LEC2 (LEAFY COTYLEDON 2), FUSCA (FUSCA3), and ABI3 (ABSCISIC ACID INSENSITIVE 3), which are directly involved in both zygotic and somatic embryogenesis. This study aimed to identify and analyze the expression profile of AFL subfamily genes during in vitro induction of the somatic embryogenesis in the model legume Medicago using near-isogenic genotypes contrasting for their capability of regenerating in vitro. Three AFL genes were identified in the Medicago truncatula genome: MtLEC2, MtFUSCA3 and MtABI3. RT-qPCR was used to compare the expression of these genes during the induction of somatic embryogenesis in the embryogenic genotype M9-10a and the non-embryogenic genotype M9. The AFL genes identified were highly expressed 10 days after introducing leaflet explants in vitro in the embryogenic genotype (M9-10a), whereas absence or low expression was observed in explants of the non-embryogenic genotype (M9). During zygotic embryogenesis, the Medicago Gene Atlas revealed that expression of MtFUSCA3 and MtABI3 occurred specifically during seed development, starting at 10 days after pollination. This study allowed for the identification and transcriptional characterization of MtLEC2, MtFUSCA3, and MtABI3. The expression pattern of these genes in the M9-10a genotype suggests they are involved in the Medicago truncatula somatic embryogenesis. The transcriptional profile of AFL transcription factors highlights the evolutionary conservation of this developmental pathway between the Arabidopsis and Medicago lineages and opens avenues to improve the efficiency of in vitro embryogenesis in legume crops.
KW - Fabaceae
KW - Gene regulation
KW - Micropropagation
KW - Plant tissue culture
UR - http://www.scopus.com/inward/record.url?scp=85071760582&partnerID=8YFLogxK
U2 - 10.1007/s11240-019-01687-3
DO - 10.1007/s11240-019-01687-3
M3 - Article
AN - SCOPUS:85071760582
VL - 139
SP - 327
EP - 337
JO - Plant Cell Tissue And Organ Culture
JF - Plant Cell Tissue And Organ Culture
SN - 0167-6857
IS - 2
ER -