Ksenia V Strygina1, Elena K Khlestkina2,3,4. 1. Institute of Cytology and Genetics, Siberian Branch of the Russian Academy of Sciences, Lavrentjeva ave. 10, Novosibirsk, 630090, Russia. pushpandzhali@bionet.nsc.ru. 2. Institute of Cytology and Genetics, Siberian Branch of the Russian Academy of Sciences, Lavrentjeva ave. 10, Novosibirsk, 630090, Russia. 3. Novosibirsk State University, Pirogova str., 1, Novosibirsk, 630090, Russia. 4. N.I. Vavilov All-Russian Research Institute of Plant Genetic Resources (VIR), Bolshaya Morskaya Str., 42-44, St. Petersburg, 190000, Russia.
Abstract
BACKGROUND: The members of the Triticeae tribe are characterised by the presence of orthologous and homoeologous gene copies regulating flavonoid biosynthesis. Among transcription factors constituting a regulatory MBW complex, the greatest contribution to the regulation of flavonoid biosynthetic pathway is invested by R2R3-Myb-type TFs. Differently expressed R2R3-Myb copies activate the synthesis of various classes of flavonoid compounds in different plant tissues. The aim of this research was the identification, comparison and analysis of full-length sequences of the duplicated R2R3-Myb Mpc1 (Myb protein c1) gene copies in barley and wheat genomes. RESULTS: The Mpc1 genes were identified in homoeologous group 4 and 7 chromosomes: a total of 3 copies in barley (Hordeum vulgare L.) and 8 copies in bread wheat (Triticum aestivum L.) genomes. All Mpc1 genes have a similar two-exon structure, and almost all of them are transcriptionally active. The calculation of the divergence time revealed that first duplication between 4 and 7 chromosomes of the common ancestor of the Triticeae tribe occurred about 35-46 million years ago (MYA); the last duplication arised about 16-19 MYA before the divergence Triticum and Hordeum genera The connection between gene expression and the appearance of anthocyanin pigmentation was found for three genes from homoeologous group 4 chromosomes: TaMpc1-A2 (5AL) in wheat coleoptile, HvMpc1-H2 (4HL) in barley lemma and aleurone layer, and HvMpc1-H3 (4HL) in barley aleurone layer. TaMpc1-D4 (4DL) from the wheat genome showed a strong level of expression regardless of the colour of coleoptile or pericarp. It is assumed, that this gene regulates the biosynthesis of uncoloured flavonoids in analysed tissues. CONCLUSIONS: The regulatory R2R3-Myb genes involved in anthocyanin synthesis were identified and characterised in Triticeae tribe species. Genes designated HvMpc1-H2 and HvMpc1-H3 appeared to be the main factors underlying intraspecific variation of H. vulgare by lemma and aleurone colour. TaMpc1-A2 is the co-regulator of the Mpc1-1 genes in bread wheat genome controlling anthocyanin synthesis in coleoptile.
BACKGROUND: The members of the Triticeae tribe are characterised by the presence of orthologous and homoeologous gene copies regulating flavonoid biosynthesis. Among transcription factors constituting a regulatory MBW complex, the greatest contribution to the regulation of flavonoid biosynthetic pathway is invested by R2R3-Myb-type TFs. Differently expressed R2R3-Myb copies activate the synthesis of various classes of flavonoid compounds in different plant tissues. The aim of this research was the identification, comparison and analysis of full-length sequences of the duplicated R2R3-Myb Mpc1 (Myb protein c1) gene copies in barley and wheat genomes. RESULTS: The Mpc1 genes were identified in homoeologous group 4 and 7 chromosomes: a total of 3 copies in barley (Hordeum vulgare L.) and 8 copies in bread wheat (Triticum aestivum L.) genomes. All Mpc1 genes have a similar two-exon structure, and almost all of them are transcriptionally active. The calculation of the divergence time revealed that first duplication between 4 and 7 chromosomes of the common ancestor of the Triticeae tribe occurred about 35-46 million years ago (MYA); the last duplication arised about 16-19 MYA before the divergence Triticum and Hordeum genera The connection between gene expression and the appearance of anthocyaninpigmentation was found for three genes from homoeologous group 4 chromosomes: TaMpc1-A2 (5AL) in wheat coleoptile, HvMpc1-H2 (4HL) in barley lemma and aleurone layer, and HvMpc1-H3 (4HL) in barley aleurone layer. TaMpc1-D4 (4DL) from the wheat genome showed a strong level of expression regardless of the colour of coleoptile or pericarp. It is assumed, that this gene regulates the biosynthesis of uncoloured flavonoids in analysed tissues. CONCLUSIONS: The regulatory R2R3-Myb genes involved in anthocyanin synthesis were identified and characterised in Triticeae tribe species. Genes designated HvMpc1-H2 and HvMpc1-H3 appeared to be the main factors underlying intraspecific variation of H. vulgare by lemma and aleurone colour. TaMpc1-A2 is the co-regulator of the Mpc1-1 genes in bread wheat genome controlling anthocyanin synthesis in coleoptile.
Authors: Jérôme Salse; Michael Abrouk; Stéphanie Bolot; Nicolas Guilhot; Emmanuel Courcelle; Thomas Faraut; Robbie Waugh; Timothy J Close; Joachim Messing; Catherine Feuillet Journal: Proc Natl Acad Sci U S A Date: 2009-08-13 Impact factor: 11.205
Authors: Michael G Francki; Grantley S Stainer; Esther Walker; Gregory J Rebetzke; Katia T Stefanova; Robert J French Journal: Front Plant Sci Date: 2021-12-24 Impact factor: 5.753