<i>Tropaeolum majus</i> R2R3 MYB Transcription Factor TmPAP2 Functions as a Positive Regulator of Anthocyanin Biosynthesis
Anthocyanins are an important group of water-soluble and non-toxic natural pigments with antioxidant and anti-inflammatory properties that can be found in flowers, vegetables, and fruits. Anthocyanin biosynthesis is regulated by several different types of transcription factors, including the WD40-re...
Main Authors: | , , , , |
---|---|
Format: | Article |
Language: | English |
Published: |
MDPI AG
2022-10-01
|
Series: | International Journal of Molecular Sciences |
Subjects: | |
Online Access: | https://www.mdpi.com/1422-0067/23/20/12395 |
_version_ | 1797431583195529216 |
---|---|
author | Xiaoping Wang Wei Wang Siyu Chen Yuji Lian Shucai Wang |
author_facet | Xiaoping Wang Wei Wang Siyu Chen Yuji Lian Shucai Wang |
author_sort | Xiaoping Wang |
collection | DOAJ |
description | Anthocyanins are an important group of water-soluble and non-toxic natural pigments with antioxidant and anti-inflammatory properties that can be found in flowers, vegetables, and fruits. Anthocyanin biosynthesis is regulated by several different types of transcription factors, including the WD40-repeat protein Transparent Testa Glabra 1 (TTG1), the bHLH transcription factor Transparent Testa 8 (TT8), Glabra3 (GL3), Enhancer of GL3 (EGL3), and the R2R3 MYB transcription factor Production of Anthocyanin Pigment 1 (PAP1), PAP2, MYB113, and MYB114, which are able to form MYB-bHLH-WD40 (MBW) complexes to regulate the expression of late biosynthesis genes (LBGs) in the anthocyanin biosynthesis pathway. Nasturtium (<i>Tropaeolum majus</i>) is an edible flower plant that offers many health benefits, as it contains numerous medicinally important ingredients, including anthocyanins. By a comparative examination of the possible anthocyanin biosynthesis regulator genes in nasturtium varieties with different anthocyanin contents, we found that <i>TmPAP2</i>, an R2R3 MYB transcription factor gene, is highly expressed in “Empress of India”, a nasturtium variety with high anthocyanin content, while the expression of <i>TmPAP2</i> in <i>Arabidopsis</i> led to the overproduction of anthocyanins. Protoplast transfection shows that TmPAP2 functions as a transcription activator; consistent with this finding, some of the biosynthesis genes in the general phenylpropanoid pathway and anthocyanin biosynthesis pathway were highly expressed in “Empress of India” and the <i>35S:TmPAP2</i> transgenic <i>Arabidopsis</i> plants. However, protoplast transfection indicates that TmPAP2 may not be able to form an MBW complex with TmGL3 and TmTTG1. These results suggest that TmPAP2 may function alone as a key regulator of anthocyanin biosynthesis in nasturtiums. |
first_indexed | 2024-03-09T09:47:15Z |
format | Article |
id | doaj.art-ca7d14220d8546c1a9f9a3ed16a2bc73 |
institution | Directory Open Access Journal |
issn | 1661-6596 1422-0067 |
language | English |
last_indexed | 2024-03-09T09:47:15Z |
publishDate | 2022-10-01 |
publisher | MDPI AG |
record_format | Article |
series | International Journal of Molecular Sciences |
spelling | doaj.art-ca7d14220d8546c1a9f9a3ed16a2bc732023-12-02T00:32:32ZengMDPI AGInternational Journal of Molecular Sciences1661-65961422-00672022-10-0123201239510.3390/ijms232012395<i>Tropaeolum majus</i> R2R3 MYB Transcription Factor TmPAP2 Functions as a Positive Regulator of Anthocyanin BiosynthesisXiaoping Wang0Wei Wang1Siyu Chen2Yuji Lian3Shucai Wang4Laboratory of Plant Molecular Genetics & Crop Gene Editing, School of Life Sciences, Linyi University, Linyi 276000, ChinaLaboratory of Plant Molecular Genetics & Crop Gene Editing, School of Life Sciences, Linyi University, Linyi 276000, ChinaLaboratory of Plant Molecular Genetics & Crop Gene Editing, School of Life Sciences, Linyi University, Linyi 276000, ChinaLaboratory of Plant Molecular Genetics & Crop Gene Editing, School of Life Sciences, Linyi University, Linyi 276000, ChinaLaboratory of Plant Molecular Genetics & Crop Gene Editing, School of Life Sciences, Linyi University, Linyi 276000, ChinaAnthocyanins are an important group of water-soluble and non-toxic natural pigments with antioxidant and anti-inflammatory properties that can be found in flowers, vegetables, and fruits. Anthocyanin biosynthesis is regulated by several different types of transcription factors, including the WD40-repeat protein Transparent Testa Glabra 1 (TTG1), the bHLH transcription factor Transparent Testa 8 (TT8), Glabra3 (GL3), Enhancer of GL3 (EGL3), and the R2R3 MYB transcription factor Production of Anthocyanin Pigment 1 (PAP1), PAP2, MYB113, and MYB114, which are able to form MYB-bHLH-WD40 (MBW) complexes to regulate the expression of late biosynthesis genes (LBGs) in the anthocyanin biosynthesis pathway. Nasturtium (<i>Tropaeolum majus</i>) is an edible flower plant that offers many health benefits, as it contains numerous medicinally important ingredients, including anthocyanins. By a comparative examination of the possible anthocyanin biosynthesis regulator genes in nasturtium varieties with different anthocyanin contents, we found that <i>TmPAP2</i>, an R2R3 MYB transcription factor gene, is highly expressed in “Empress of India”, a nasturtium variety with high anthocyanin content, while the expression of <i>TmPAP2</i> in <i>Arabidopsis</i> led to the overproduction of anthocyanins. Protoplast transfection shows that TmPAP2 functions as a transcription activator; consistent with this finding, some of the biosynthesis genes in the general phenylpropanoid pathway and anthocyanin biosynthesis pathway were highly expressed in “Empress of India” and the <i>35S:TmPAP2</i> transgenic <i>Arabidopsis</i> plants. However, protoplast transfection indicates that TmPAP2 may not be able to form an MBW complex with TmGL3 and TmTTG1. These results suggest that TmPAP2 may function alone as a key regulator of anthocyanin biosynthesis in nasturtiums.https://www.mdpi.com/1422-0067/23/20/12395nasturtium<i>Tropaeolum majus</i>anthocyanin biosynthesistranscription factorsTmPAP2TmTTG1 |
spellingShingle | Xiaoping Wang Wei Wang Siyu Chen Yuji Lian Shucai Wang <i>Tropaeolum majus</i> R2R3 MYB Transcription Factor TmPAP2 Functions as a Positive Regulator of Anthocyanin Biosynthesis International Journal of Molecular Sciences nasturtium <i>Tropaeolum majus</i> anthocyanin biosynthesis transcription factors TmPAP2 TmTTG1 |
title | <i>Tropaeolum majus</i> R2R3 MYB Transcription Factor TmPAP2 Functions as a Positive Regulator of Anthocyanin Biosynthesis |
title_full | <i>Tropaeolum majus</i> R2R3 MYB Transcription Factor TmPAP2 Functions as a Positive Regulator of Anthocyanin Biosynthesis |
title_fullStr | <i>Tropaeolum majus</i> R2R3 MYB Transcription Factor TmPAP2 Functions as a Positive Regulator of Anthocyanin Biosynthesis |
title_full_unstemmed | <i>Tropaeolum majus</i> R2R3 MYB Transcription Factor TmPAP2 Functions as a Positive Regulator of Anthocyanin Biosynthesis |
title_short | <i>Tropaeolum majus</i> R2R3 MYB Transcription Factor TmPAP2 Functions as a Positive Regulator of Anthocyanin Biosynthesis |
title_sort | i tropaeolum majus i r2r3 myb transcription factor tmpap2 functions as a positive regulator of anthocyanin biosynthesis |
topic | nasturtium <i>Tropaeolum majus</i> anthocyanin biosynthesis transcription factors TmPAP2 TmTTG1 |
url | https://www.mdpi.com/1422-0067/23/20/12395 |
work_keys_str_mv | AT xiaopingwang itropaeolummajusir2r3mybtranscriptionfactortmpap2functionsasapositiveregulatorofanthocyaninbiosynthesis AT weiwang itropaeolummajusir2r3mybtranscriptionfactortmpap2functionsasapositiveregulatorofanthocyaninbiosynthesis AT siyuchen itropaeolummajusir2r3mybtranscriptionfactortmpap2functionsasapositiveregulatorofanthocyaninbiosynthesis AT yujilian itropaeolummajusir2r3mybtranscriptionfactortmpap2functionsasapositiveregulatorofanthocyaninbiosynthesis AT shucaiwang itropaeolummajusir2r3mybtranscriptionfactortmpap2functionsasapositiveregulatorofanthocyaninbiosynthesis |