Pectinase and cellulase participate in cell wall degradation during secretory cavity formation in Citrus fruits. However, it remains unknown how secretory cavity formation is regulated by pectinase and cellulase genes in a schizolysigenous model. Our Results showed that PCD was involved in the schizolysigenous formation of the secretory cavities, and pectinase was involved in the degradation of the middle lamella while pectinase combined with cellulase were responsible for the degradation of the primary cell wall. Furthermore, the expression levels of CisPG21 and CisCEL16 at the intercellular space-forming and lumen-expanding stages with the continuous degradation of the cell wall were significantly higher than those at the initial cell stage and mature stage. The in situ hybridization (ISH) results also showed that CisPG21 and CisCEL16 were mainly located in the degrading cells of secretory cavities, and signals were very strong at the intercellular space-forming and lumen-expanding stages. In conclusion, pectinase and cellulase are directly involved in the degradation of PCD cell walls during schizolysigenous formation in the secretary cavity of Citrus sinensis (L.) Osbeck fruit, while CisPG21 and CisCEL16 are important regulatory genes of pectinase and cellulose during cell wall degradation.

中文翻译：

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Citrus sinensis (L.) Osbeck 果实分泌腔细胞程序性细胞死亡过程中，CisPG21 和 CisCEL16 参与调节细胞壁降解

果胶酶和纤维素酶参与柑橘类水果分泌腔形成过程中的细胞壁降解。然而，在裂殖体模型中，果胶酶和纤维素酶基因如何调节分泌腔的形成仍然未知。我们的结果表明，PCD 参与了分泌腔的分裂溶解性形成，果胶酶参与了中层的降解，而果胶酶与纤维素酶的结合负责了初级细胞壁的降解。此外，随着细胞壁的不断降解，CisPG21和CisCEL16在细胞间隙形成和管腔扩张阶段的表达水平显着高于细胞初始阶段和成熟阶段。原位杂交（ISH）结果还表明，CisPG21和CisCEL16主要位于分泌腔的降解细胞中，在细胞间隙形成和腔扩张阶段信号很强。总之，果胶酶和纤维素酶直接参与了Citrus sinensis (L.) Osbeck 果实秘书腔裂殖溶解形成过程中PCD 细胞壁的降解，而CisPG21 和CisCEL16 是细胞壁降解过程中果胶酶和纤维素的重要调控基因。