Sina and Sinb genes in triticale do not determine grain hardness contrary to their orthologs Pina and Pinb in wheat

BMC Plant Biology

Research Article

Anna Nadolska-Orczyk¹  Sebastian Gasparis¹  Waclaw Orczyk² 

[1] Department of Functional Genetics, Plant Breeding and Acclimatization Institute – National Research Institute, 05-870, Radzikow, Blonie, Poland;Department of Genetic Engineering, Plant Breeding and Acclimatization Institute – National Research Institute, 05-870, Radzikow, Blonie, Poland;

关键词: RNAi silencing;    Sin;    Triticale;    Secaloindoline;    Wheat;    Puroindoline;    Agrobacterium;    Gene function;    Orthologs;   

DOI  :  10.1186/1471-2229-13-190

 received in 2013-10-09, accepted in 2013-11-20,  发布年份 2013

来源: Springer

【 摘 要 】

BackgroundSecaloindoline a (Sina) and secaloindoline b (Sinb) genes of hexaploid triticale (x Triticosecale Wittmack) are orthologs of puroindoline a (Pina) and puroindoline b (Pinb) in hexaploid wheat (Triticum aestivum L.). It has already been proven that RNA interference (RNAi)-based silencing of Pina and Pinb genes significantly decreased the puroindoline a and puroindoline b proteins in wheat and essentially increased grain hardness (J Exp Bot 62:4025-4036, 2011). The function of Sina and Sinb in triticale was tested by means of RNAi silencing and compared to wheat.ResultsNovel Sina and Sinb alleles in wild-type plants of cv. Wanad were identified and their expression profiles characterized. Alignment with wheat Pina-D1a and Pinb-D1a alleles showed 95% and 93.3% homology with Sina and Sinb coding sequences. Twenty transgenic lines transformed with two hpRNA silencing cassettes directed to silence Sina or Sinb were obtained by the Agrobacterium-mediated method. A significant decrease of expression of both Sin genes in segregating progeny of tested T1 lines was observed independent of the silencing cassette used. The silencing was transmitted to the T4 kernel generation. The relative transcript level was reduced by up to 99% in T3 progeny with the mean for the sublines being around 90%. Silencing of the Sin genes resulted in a substantial decrease of secaloindoline a and secaloindoline b content. The identity of SIN peptides was confirmed by mass spectrometry. The hardness index, measured by the SKCS (Single Kernel Characterization System) method, ranged from 22 to 56 in silent lines and from 37 to 49 in the control, and the mean values were insignificantly lower in the silent ones, proving increased softness. Additionally, the mean total seed protein content of silenced lines was about 6% lower compared with control lines. Correlation coefficients between hardness and transcript level were weakly positive.ConclusionsWe documented that RNAi-based silencing of Sin genes resulted in significant decrease of their transcripts and the level of both secaloindoline proteins, however did not affect grain hardness. The unexpected, functional differences of Sin genes from triticale compared with their orthologs, Pin of wheat, are discussed.

【 授权许可】

Unknown   
© Gasparis et al.; licensee BioMed Central Ltd. 2013. This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.