Centro Andaluz de Biología del Desarrollo, Universidad Pablo de Olavide-Consejo Superior de Investigaciones Científicas-Junta de Andalucía, 41013 Seville, Spain.
Department of Cell Biology, Faculty of Biology, University of Seville, 41012 Seville, Spain.
Int J Mol Sci. 2021 Dec 28;23(1):303. doi: 10.3390/ijms23010303.
Cell division produces two viable cells of a defined size. Thus, all cells require mechanisms to measure growth and trigger cell division when sufficient growth has occurred. Previous data suggest a model in which growth rate and cell size are mechanistically linked by ceramide-dependent signals in budding yeast. However, the conservation of mechanisms that govern growth control is poorly understood. In fission yeast, ceramide synthase is encoded by two genes, Lac1 and Lag1. Here, we characterize them by using a combination of genetics, microscopy, and lipid analysis. We showed that Lac1 and Lag1 co-immunoprecipitate and co-localize at the endoplasmic reticulum. However, each protein generates different species of ceramides and complex sphingolipids. We further discovered that Lac1, but not Lag1, is specifically required for proper control of cell growth and size in . We propose that specific ceramide and sphingolipid species produced by Lac1 are required for normal control of cell growth and size in fission yeast.
细胞分裂会产生两个具有特定大小的存活细胞。因此，所有细胞都需要有机制来测量生长并在生长达到足够程度时触发细胞分裂。先前的数据表明，在出芽酵母中，通过依赖神经酰胺的信号，生长速率和细胞大小在机制上是相关的。然而，控制生长的机制的保守性理解很差。在裂殖酵母中，神经酰胺合酶由两个基因 Lac1 和 Lag1 编码。在这里，我们通过遗传学、显微镜和脂质分析的组合来对它们进行了表征。我们表明 Lac1 和 Lag1 可以共免疫沉淀并共定位于内质网。然而，每种蛋白质都会产生不同种类的神经酰胺和复杂的鞘脂。我们还发现 Lac1 而不是 Lag1 ，是裂殖酵母中细胞生长和大小正常控制所必需的。我们提出，由 Lac1 产生的特定神经酰胺和鞘脂种类是裂殖酵母中细胞生长和大小正常控制所必需的。
