A ZYGOTE‐SPECIFIC PROTEIN WITH HYDROXYPROLINE‐RICH GLYCOPROTEIN DOMAINS AND LECTIN‐LIKE DOMAINS INVOLVED IN THE ASSEMBLY OF THE CELL WALL OF CHLAMYDOMONAS REINHARDTII (CHLOROPHYTA)

摘要: The cell wall of Chlamydomonas reinhardtii zygotes, which forms rapidly after the fusion wall-free gametes, provides a tractable system for studying properties and assembly hydroxyproline-rich glycoproteins, major proteinaceous components green algal plant walls. We report cloning zsp2 gene analysis its ZSP-2 product, 58.9 kDa polypeptide that is synthesized exclusively by zygotes. protein contains two (SP)x repeats, establishing it as member glycoproteins family. It also 4-fold iteration an amino acid sequence centered around cysteine residues, configuration found in both animal lectins. Furthermore, we four observations on pellicle composition production. First, cell-free preparations matrix are rich hydroxyproline, arabinose, galactose contain bundles very long fibrils. Second, glutathione blocks formation results accumulation fibrils growth medium. Third, antibody to formation. Fourth, immunolocalizes boundary between outer layers proper matrix. These consistent with possibility Cys-rich (glutathione-sensitive) lectin-like domains may bind sugar residues anchor them wall, thereby initiating maintaining