Department of Cell and Development Biology, College of Life Science, State Key Laboratory of Plant Hybrid Rice, Wuhan University, Wuhan 430072, China.
Dev Cell. 2012 Nov 13;23(5):1043-58. doi: 10.1016/j.devcel.2012.09.011. Epub 2012 Oct 18.
Cell-to-cell communication in embryo sacs is thought to regulate the development of female gametes in flowering plants, but the details remain poorly understood. Here, we report a mitochondrial protein, GAMETE CELL DEFECTIVE 1 (GCD1), enriched in gametophytes that is essential for final maturation of female gametes. Using Arabidopsis gcd1 mutants, we found that final maturation of the egg and central cells is not required for double fertilization but is necessary for embryogenesis initiation and endosperm development. Furthermore, nonautonomous effects, observed when GCD1 or AAC2 function is disrupted, suggest that mitochondrial function influences reciprocal signaling between central and egg cells to regulate maturation of the partner (egg or central) cell. Our findings confirm that cell-to-cell communication is important in functional maturation of female gametic cells and suggest that both egg and central cells sense and transmit their mitochondrial metabolic status as an important cue that regulates the coordination of gamete maturation.
囊胚细胞间的通讯被认为可以调节开花植物中雌性配子的发育，但其中的细节仍知之甚少。在这里，我们报告了一种富含于配子体中的线粒体蛋白 GAMETE CELL DEFECTIVE 1（GCD1），它对于雌性配子的最终成熟是必需的。利用拟南芥 gcd1 突变体，我们发现双受精并不需要卵母细胞和中央细胞的最终成熟，但对于胚胎发生的起始和胚乳发育是必需的。此外，当 GCD1 或 AAC2 的功能被破坏时观察到的非自主性效应表明，线粒体功能影响中央细胞和卵母细胞之间的相互信号传递，以调节伙伴（卵母细胞或中央细胞）的成熟。我们的研究结果证实，细胞间通讯在雌性配子细胞的功能成熟中是重要的，并表明卵母细胞和中央细胞都能感知和传递其线粒体代谢状态，作为调节配子成熟协调的重要信号。
