Autophagy triggers CTSD (cathepsin D) maturation and localization inside cells to promote apoptosis
Autophagy triggers CTSD (cathepsin D) maturation and localization inside cells to promote apoptosis
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自噬触发 CTSD（组织蛋白酶 D）在细胞内成熟和定位以促进细胞凋亡
DOI：
10.1080/15548627.2020.1752497
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发表时间：
2020-04-23
期刊：
影响因子：
13.3
通讯作者：
Zhao, Xiao-Fan
中科院分区：
文献类型：
--
作者：
Di, Yu-Qin;Han, Xiao-Lin;Zhao, Xiao-Fan
摘要CTSD/caxD/CATD(组织蛋白酶D)是一种溶酶体天冬氨酸蛋白酶。CTSD的一个显著特征是它的双重功能，即通过分泌细胞外的酶原作为配体促进细胞增殖，以及通过该酶的成熟形式促进细胞内的凋亡；然而，其分泌、表达和成熟的调节尚不确定。以鳞翅目昆虫棉铃虫为模型，揭示了CTSD的分泌、表达和成熟的双重功能及其调控机制。天冬酰胺233(N233)的糖基化决定了原CTSD的分泌。类固醇激素20-羟基蜕皮酮(20E)促进CTSD的表达。巨噬/自噬触发CTSD成熟并定位于中肠细胞内，激活CASP3(Caspase3)，促进细胞凋亡。原CTSD在蛹的表皮中表达，并分泌到血淋巴中，促进成体脂肪体的内复制/内复制、细胞增殖和联合。我们的研究表明，CTSD在组织中的差异表达和自噬介导的成熟决定了它在细胞凋亡和细胞增殖中的作用，从而决定了鳞翅目昆虫变态过程中组织的细胞命运。缩写：20E：20-羟基蜕皮酮；3-MA：3-甲基腺嘌呤；ACTB/β-肌动蛋白：肌动蛋白β；AKT：蛋白激酶B；ATG1：自噬相关1；ATG4：自噬相关4；ATG5：自噬相关5；ATG7：自噬相关7；ATG14：自噬相关14；BSA：牛血清白蛋白；CASP3：半胱氨酸酶3；CQ：氯喹；CTSD：组织蛋白D；DAPI：4‘，6-二氨基-2-苯丙氨酸；DPBS：Dulbecco’s磷酸盐水；dsRNA：双链核糖核酸相关14；ECR：ECONE受体；ECRE：ECRE反应障碍元件；组织蛋白酶D；DAPI：4‘，6-二氨基-2-苯丙氨酸；DMSO：二甲基亚硫醚；DPBS：Dulbecco’s磷酸盐水化合物；dsRNA：双链核糖核酸相关14；ECR：蜕皮酮受体；ECRE：econe应答异常元件；EDU：5-乙炔基-2‘-脱氧尿苷；G-m-CTSD：糖基化-CTSD；G-ProCTSD：糖基化-CTSD；HAEPI：棉铃虫表皮细胞系；HE染色：苏木素和伊红染色；免疫球蛋白G；IM：假想中肠；JH：保幼激素；Kr-H1：Krueppel同源蛋白1；LM：幼虫中肠；M6P：甘露糖-6-磷酸；PBS：磷酸缓冲液；PCD：细胞程序性死亡；PNGase：肽-N-糖苷酶F；RFP：红色荧光蛋白；RNAi：RNA干扰；SDS-PAGE：十二烷基硫酸钠-聚酰胺凝胶电泳；SYX17：语法蛋白17；USP1：超阿司匹林异构体1。
ABSTRACT CTSD/CathD/CATD (cathepsin D) is a lysosomal aspartic protease. A distinguishing characteristic of CTSD is its dual functions of promoting cell proliferation via secreting a pro-enzyme outside the cells as a ligand, and promoting apoptosis via the mature form of this enzyme inside cells; however, the regulation of its secretion, expression, and maturation is undetermined. Using the lepidopteran insect Helicoverpa armigera, a serious agricultural pest, as a model, we revealed the dual functions and regulatory mechanisms of CTSD secretion, expression, and maturation. Glycosylation of asparagine 233 (N233) determined pro-CTSD secretion. The steroid hormone 20-hydroxyecdysone (20E) promoted CTSD expression. Macroautophagy/autophagy triggered CTSD maturation and localization inside midgut cells to activate CASP3 (caspase 3) and promote apoptosis. Pro-CTSD was expressed in the pupal epidermis and was secreted into the hemolymph to promote adult fat body endoreplication/endoreduplication, cell proliferation, and association. Our study revealed that the differential expression and autophagy-mediated maturation of CTSD in tissues determine its roles in apoptosis and cell proliferation, thereby determining the cell fates of tissues during lepidopteran metamorphosis. Abbreviations: 20E: 20-hydroxyecdysone; 3-MA: 3-methyladenine; ACTB/β-actin: actin beta; AKT: protein kinase B; ATG1: autophagy-related 1; ATG4: autophagy-related 4; ATG5: autophagy-related 5; ATG7: autophagy-related 7; ATG14: autophagy-related 14; BSA: bovine serum albumin; CASP3: caspase 3; CQ: choroquine; CTSD: cathepsin D; DAPI: 4′,6-diamidino-2-phenylindole; DMSO: dimethyl sulfoxide; DPBS: dulbecco’s phosphate-buffered saline; DsRNA: double-stranded RNA; EcR: ecdysone receptor; EcRE: ecdysone response element; EdU: 5-ethynyl-2´-deoxyuridine; G-m-CTSD: glycosylated-mautre-CTSD; G-pro-CTSD: glycosylated-pro-CTSD; HaEpi: Helicoverpa armigera epidermal cell line; HE staining: hematoxylin and eosin staining; IgG: immunoglobin G; IM: imaginal midgut; JH: juvenile hormone; Kr-h1: krueppel homologous protein 1; LM: larval midgut; M6P: mannose-6-phosphate; PBS: phosphate-buffered saline; PCD: programmed cell death; PNGase: peptide-N-glycosidase F; RFP: red fluorescent protein; RNAi: RNA interference; SDS-PAGE: sodium dodecyl sulfate-polyacrylamide gel electrophoresis; SYX17: syntaxin 17; USP1: ultraspiracle isoform 1.