Mancini Micaela, Permingeat Hugo, Colono Carolina, Siena Lorena, Pupilli Fulvio, Azzaro Celeste, de Alencar Dusi Diva Maria, de Campos Carneiro Vera Tavares, Podio Maricel, Seijo José Guillermo, González Ana María, Felitti Silvina A, Ortiz Juan Pablo A, Leblanc Olivier, Pessino Silvina C
Instituto de Investigaciones en Ciencias Agrarias de Rosario, CONICET-UNR, Facultad de Ciencias Agrarias, Universidad Nacional de Rosario, Zavalla, Argentina.
Istituto di Bioscienze e BioRisorse, Consiglio Nazionale delle Ricerche, Perugia, Italy.
Front Plant Sci. 2018 Oct 24;9:1547. doi: 10.3389/fpls.2018.01547. eCollection 2018.
Apomixis is a clonal mode of reproduction via seeds, which results from the failure of meiosis and fertilization in the sexual female reproductive pathway. In previous transcriptomic surveys, we identified a mitogen-activated protein kinase kinase kinase (N46) displaying differential representation in florets of sexual and apomictic genotypes. Here, we retrieved and characterized the N46 full cDNA sequence from sexual and apomictic floral transcriptomes. Phylogenetic analyses showed that N46 was a member of the family, which was re-named (). Differential expression in florets of sexual and apomictic plants was confirmed by qPCR. hybridization experiments revealed expression in the nucellus of aposporous plants' ovules, which was absent in sexual plants. RNAi inhibition of expression in two apomictic genotypes resulted in significantly reduced rates of aposporous embryo sac formation, with respect to the level detected in wild type aposporous plants and transformation controls. The locus segregated independently of apospory. However, a probe derived from a related long non-coding RNA sequence () revealed RFLP bands cosegregating with the apospory-controlling region (ACR). is expressed in florets of apomictic plants only. Our results indicate that the activity of in the nucellus of apomictic plants is necessary to form non-reduced embryo sacs and that a long non-coding sequence with regulatory potential is similar to sequences located within the ACR.
无融合生殖是一种通过种子进行的克隆繁殖方式，它源于有性雌性生殖途径中减数分裂和受精的失败。在之前的转录组学调查中，我们鉴定出一种丝裂原活化蛋白激酶激酶激酶（N46），其在有性和无融合生殖基因型的小花中表现出差异表达。在这里，我们从有性和无融合生殖的花转录组中检索并鉴定了N46的全长cDNA序列。系统发育分析表明，N46是该家族的一个成员，该家族被重新命名为（）。通过qPCR证实了N46在有性和无融合生殖植物小花中的差异表达。杂交实验揭示了无孢子生殖植物胚珠珠心细胞中有表达，而有性生殖植物中没有。在两种无融合生殖基因型中对N46表达进行RNA干扰抑制，相对于野生型无孢子生殖植物和转化对照中检测到的水平，无孢子胚囊形成率显著降低。N46基因座与无孢子生殖独立分离。然而，一个源自相关长链非编码RNA序列（）的探针显示出与无孢子生殖控制区域（ACR）共分离的RFLP条带。N46仅在无融合生殖植物的小花中表达。我们的结果表明，无融合生殖植物珠心中N46的活性对于形成未减数胚囊是必要的，并且一个具有调控潜力的长链非编码序列与位于ACR内的序列相似。
