Career Advancement Award: The Role of Multiple Cellulases in Arabidopsis Plant Development

植物细胞壁作为许多生理过程的一部分被修饰。 用于细胞壁催化分解的最重要的一类酶是纤维素酶。 德尔坎皮略博士将试图确定纤维素酶基因参与花器官脱落（从母体脱落）在拟南芥和确定他们的功能在这个过程中。 她将检验每个花器官的分裂，即，花瓣、萼片和雄蕊是顺序和协调的，每个器官的分解需要几种类型的酶，主要涉及两类纤维素酶。 一类上调并参与组织间信号的产生和/或实际的细胞-细胞分离过程，另一类下调并参与细胞壁维持。 del Campillo博士将寻找和选择上调和下调的纤维素酶基因。 然后，她将通过原位杂交实验分析这些基因的空间和时间表达，该实验将与马里兰州大学帕克分校植物生物学系的刘忠驰博士合作进行。 她还将分析由麦迪逊麦迪逊的威斯康星州大学植物系的Anthony Bleecker博士分离的脱落缺陷突变体中纤维素酶表达的模式。德尔坎皮略博士将试图确定拟南芥T-DNA插入突变体与选定的纤维素酶基因的表达受损。 一旦获得上调和下调的水解纤维素酶的纤维素酶突变体，将尝试杂交以获得稳定的双突变体，以确定水解是否需要两种纤维素酶的协调基因表达。 所有的实验都将与布利克博士合作进行。

The plant cell wall is modified as part of many physiological processes. One of the most important classes of enzymes for cell-wall catabolism is cellulases. Dr. del Campillo will attempt to identify the cellulase genes involved in floral-organ abscission (shedding from the parent body) in Arabidopsis and to determine their function in the process. She will test the hypothesis that abscission of each floral organ, i.e., petal, sepal and stamen, is sequential and coordinated, and that abscission of each organ requires several types of enzymes and principally involves two classes of cellulases. One class is up-regulated and involved in the production of intertissue signal(s) and/or in the actual cell-cell separation process, and another class is down-regulated and involved in cell-wall maintenance. Dr. del Campillo will search for and select up-regulated and down-regulated cellulase genes. She then will analyze the spatial and temporal expression of these genes by in situ hybridization experiments to be conducted in collaboration with Dr. Zhongchi Liu in the Department of Plant Biology at the University of Maryland, College Park. She also will analyze the pattern of cellulase expression in abscission-defective mutants isolated by Dr. Anthony Bleecker in the Botany Department of the University of Wisconsin, Madison. Dr. del Campillo will attempt to identify Arabidopsis T-DNA insertional mutants with impaired expression in the selected cellulase genes. Once cellulase mutants are obtained for both the up- and down-regulated abscission cellulases, crosses will be attempted in order to obtain stable double mutants, to determine if coordinated gene expression of both cellulases is required for abscission. All abscission experiments will be conducted in collaboration with Dr. Bleecker.