title: Arabidopsis aspartic proteases A36 and A39 play roles in plant reproduction.
abstract: Aspartic proteases (Aps, EC3.4.23) are one of the 4 major mechanistic classes of proteolytic enzymes with the conserved motifs Asp-Thr/Ser-Gly (DT/SG) at the active site and are activated at acidic pH. In Arabidopsis, 69 genes were identified as coding putative aspartic proteinases. However, little is known about most of these enzymes. Recently, we characterized 2 novel Arabidopsis Aps genes, A36 and A39, which encode 2 putative GPI-anchored pollen-high-expressed Aps. a36 a39 mutants display significant abortion. The pollen grains underwent apoptosis-like programmed cell death and the degeneration of female gametes was also appeared in the a36 a39 mutant. Besides, the pollen tube of a36 a39 has compromised micropylar guidance. A36 and A39 were membrane-anchored protein and co-localized with a reported GPI-anchored protein COBRA-LIKE 10 (COBL10). In apical region of a36 a39 pollen tubes cell wall, the abundance of highly methlyestered homogalacturonans and xyloglucans were significantly increased. These results indicated that A36 and A39 are vital factors involved in gametogenesis and pollen guidance in Arabidopsis.
authors.affiliation: a Hebei Key Laboratory of Molecular and Cellular Biology , College of Life Science, Hebei Normal University , Shijia Zhuang, Hebei , P.R. China.|b Key Laboratory of Molecular and Cellular Biology of Ministry of Education , College of Life Science, Hebei Normal University , Shijia Zhuang, Hebei , P.R. China.|c Hebei Collaboration Innovation Center for Cell Signaling , Shijia Zhuang, Hebei , P.R. China.
authors.forename: Hui
authors.initials: H
authors.lastname: Gao
authors.affiliation: a Hebei Key Laboratory of Molecular and Cellular Biology , College of Life Science, Hebei Normal University , Shijia Zhuang, Hebei , P.R. China.|b Key Laboratory of Molecular and Cellular Biology of Ministry of Education , College of Life Science, Hebei Normal University , Shijia Zhuang, Hebei , P.R. China.|c Hebei Collaboration Innovation Center for Cell Signaling , Shijia Zhuang, Hebei , P.R. China.
authors.forename: Rui
authors.initials: R
authors.lastname: Li
authors.affiliation: a Hebei Key Laboratory of Molecular and Cellular Biology , College of Life Science, Hebei Normal University , Shijia Zhuang, Hebei , P.R. China.|b Key Laboratory of Molecular and Cellular Biology of Ministry of Education , College of Life Science, Hebei Normal University , Shijia Zhuang, Hebei , P.R. China.|c Hebei Collaboration Innovation Center for Cell Signaling , Shijia Zhuang, Hebei , P.R. China.
authors.forename: Yi
authors.initials: Y
authors.lastname: Guo
mesh_terms: D017360:Arabidopsis / Q000201:enzymology* / Q000235:genetics / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism; D057055:Aspartic Acid Proteases / Q000235:genetics / Q000378:metabolism*; D016923:Cell Death / Q000235:genetics / Q000502:physiology; D018506:Gene Expression Regulation, Plant / Q000235:genetics / Q000502:physiology; D011058:Pollen / Q000201:enzymology / Q000235:genetics / Q000378:metabolism; D053205:Pollen Tube / Q000235:genetics / Q000502:physiology
chemical_list: D029681:Arabidopsis Proteins; D057055:Aspartic Acid Proteases
keywords: Arabidopsis; aspartic proteases; pollen; pollen tube guidance; programmed cell death