Cách ly các kinase liên quan đến phòng thủ bằng cách nhắm mục tiêu vào miền kinase (RLK/Pelle) trong Platanus × acerifolia: phân tích hệ phát sinh chủng loài và cấu trúc

Springer Science and Business Media LLC - Tập 7 - Trang 1-22 - 2014
Massimo Pilotti1, Angela Brunetti1, Paolo Uva2, Valentina Lumia1, Lorenza Tizzani1, Fabio Gervasi3, Michele Iacono4, Massimo Pindo5
1Plant Pathology Research Center, CRA-PAV Agricultural Research Council, 00156 Rome, Italy
2CRS4 Bioinformatics Laboratory POLARIS Science and Technology Park, 09010 Pula, Cagliari, Italy
3Fruit Tree Research Center, CRA-FRU Agricultural Research Council, 00134 Rome, Italy
4Roche Diagnostics SpA, 20052 Monza, Milano, Italy
5Research and Innovation Centre, Edmund Mach Foundation, Trento, Italy

Tóm tắt

Gia đình kinase giống thụ cảm (RLK/Pelle) điều chỉnh sự sinh trưởng và các quá trình phát triển cũng như sự tương tác với các tác nhân gây bệnh và sinh vật cộng sinh. Platanaceae là một trong những nhánh sớm nhất của Eudicots, tách ra trước khi phân tách thành Rosids và Asterids. Do đó, các nghiên cứu về gia đình RLK trong Platanus có thể cung cấp thông tin về sự tiến hóa của gia đình gen này trong thực vật đất. Hơn nữa, RLKs là những ứng viên tốt để tìm kiếm các gen có thể cung cấp khả năng kháng lại các tác nhân gây bệnh ở Platanus. Các mồi oligonucleotide suy biến nhắm vào miền kinase của các RLK liên quan đến căng thẳng đã được sử dụng để phân lập lần đầu tiên 111 đoạn gen RLK trong Platanus × acerifolia. Các trình tự đã được phân loại thành các ứng viên của các tiểu họ sau: CrRLK1L, LRR XII, tương tự WAK, và nhóm LRR X-BRI1. Tất cả các đặc điểm cấu trúc điển hình của miền kinase RLK đã được xác định, bao gồm động lực không-RD, dấu hiệu của các thụ thể nhận diện tác nhân gây bệnh tiềm năng (PRRs). Các ứng viên LRR XII, tương ứng với Arabidopsis và lúa bao gồm các PRR không-RD, chủ yếu là các kinase không-RD, cho thấy một nhóm các PRR. Các dấu hiệu đặc trưng của việc lựa chọn làm sạch thoải mái trong các ứng viên LRR XII cũng đã được tìm thấy, điều này là mới trong miền kinase RLK thực vật và càng hỗ trợ vai trò của các ứng viên LRR XII như là PRR. Khi chúng tôi thu được các ứng viên CrRLK1L bằng cách sử dụng các mồi được thiết kế trên Pto của cà chua, chúng tôi đã phân tích mối quan hệ phát sinh chủng loài giữa CrRLK1L và các gen tương tự Pto của các loài thực vật. Do đó, chúng tôi đã phân loại tất cả các gen tương tự Pto không thuộc họ Solanaceae như CrRLK1L và lần đầu tiên làm nổi bật sự gần gũi trong phát sinh chủng loài giữa CrRLK1L và nhóm Pto. Nguồn gốc của Pto từ CrRLK1L được đề xuất như một cơ chế tiến hóa. Các dấu hiệu của việc lựa chọn làm sạch thoải mái nhấn mạnh rằng một nhóm các RLK có thể đã liên quan đến sự biểu hiện của tính linh hoạt biểu phen và do đó là ứng viên tốt để điều tra khả năng kháng bệnh. Tìm kiếm các gen tương tự Pto trong Platanus đã làm nổi bật mối quan hệ gần gũi giữa CrRLK1L và nhóm Pto. Sẽ rất thú vị nếu xác minh liệu có các Pto kiểu strictu ở các nhóm phân loại khác ngoài Solanaceae để làm rõ thêm mối liên hệ tiến hóa với CrRLK1L. Chúng tôi đã thu được một tài nguyên quý giá đầu tiên hữu ích cho việc nghiên cứu sâu về các hệ thống nhận diện căng thẳng.

Từ khóa


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