Cyclin-Dependent Kinase Inhibitor Gene TaICK1 acts as a Potential Contributor to Wheat Male Sterility induced by a Chemical Hybridizing Agent

Abstract

Heterosis has been widely accepted as an effective strategy to increase yields in plant breeding. Notably, the chemical hybridization agent SQ-1 induces male sterility in wheat, representing a critical potential tool in hybrid seed production. However, the mechanisms underlying the male sterility induced by SQ-1 still remain poorly understood. In this study, a cyclin-dependent kinase inhibitor gene, TaICK1, which encodes a 229 amino acid protein, was identified as a potential contributor to male sterility in common wheat. The expression of TaICK1 was upregulated during the development of anthers in Xinong1376 wheat treated with SQ-1. Meanwhile, the seed setting rate was found to be significantly decreased in TaICK1 transgenic rice. Furthermore, we identified two cyclin proteins, TaCYCD2;1 and TaCYCD6;1, as interactors through yeast two-hybrid screening using TaICK1 as the bait, which were validated using bimolecular fluorescence complementation. Subcellular localization revealed that the proteins encoded by TaICK1, TaCYCD2;1, and TaCYCD6;1 were localized in the cell nucleus. The expression levels of TaCYCD2;1 and TaCYCD6;1 were lower in Xinong1376 treated with SQ-1. A further analysis demonstrated that the expression levels of OsCYCD2;1 and OsCYCD6;1 were lower in transgenic TaICK1 rice lines as well. Taken together, these results suggest that the upregulation of TaICK1, induced by SQ-1, may subsequently suppress the expression of TaCYCD2;1 and TaCYCD6;1 in anthers, resulting in male sterility. This study provides new insights into the understanding of SQ-1-induced wheat male sterility, as well as the developmental mechanisms of anthers.

The Transcription Factors TaTDRL and TaMYB103 Synergistically Activate the Expression of TAA1a in Wheat, Which Positively Regulates the Development of Microspore in Arabidopsis

“…The stages of microspore development were identified by staining the anthers with 1% acetocarmine and 2% I 2 -KI. Samples were photographed using a DS-U2 high-resolution camera mounted on a Nikon ECLIPSE E600 fluorescence microscope (Nikon, ECLIPSE, E600, Tokyo, Japan) and analyzed using NIS-Elements software (Nikon, Tokyo, Japan) [ 12 , 82 ].…”

“…Heterosis refers to a phenomenon in which the F1 generation of genetically diverse individuals of the same species is superior to the parents in aspects such as yield, stress resistance, and adaptability [ 9 , 10 ]. Accordingly, the utilization of heterosis in wheat breeding represents one of the most effective strategies for improving the yield of this crop [ 11 , 12 ].…”

Genome-wide identification and expression analysis of kinesin genes superfamily suggested their roles in response to abiotic stress and fertility of wheat (Triticum aestivum L.)

“…Studies have shown that abnormal division of microspore during gametogenesis can lead to male sterility, and abnormal division may be caused by abnormal microtubules [29]. Our previous studies found that meiosis and mitosis are abnormal in development of cytoplasm male sterile (CMS) lines in wheat [30][31][32].…”

“…Wheat (Triticum aestivum L.) is one of the most important crops in the world, delivers around 20% of our food calories and protein, and feeds nearly 40% of the world's population [27,28].As the growth of the population and the changing of the global climate conditions, wheat breeding faces greater challenges. Heterosis utilization offered one of the most effective strategies for improving the yield and resisting the adverse natural environment [29]. Although cytoplasm male sterility is a much more effective in producing hybrid, the mechanisms of male sterile is still mystery.…”

Deletion of a cyclin-dependent protein kinase inhibitor, CsSMR1, leads to dwarf and determinate growth in cucumber (Cucumis sativus L.)

“…There were two types of plant-specific CKI in land plants, known as Inhibitor/Interactor of CDC2 Kinase/KIP-related proteins (ICK/KRPs) and SIAMESE-related proteins (SMRs), of which SIM is the founding member. Among them, ICK/KRP members were reported to play diversity roles in root initiation, xylem pericycle development, pollen fertility, fruit enlargement and seed-setting (Brady 2019 ; Nafati et al 2011 ; Wen et al 2013 ; Yang et al 2011 ; Zhang et al 2020 ). The SMRs were identified later than ICK/KRPs and have limited studies over the past few years.…”