Naslov
Evolution of CBP60 protein family, which includes subfamilies of major regulators of SA-mediated immune response

Autori
Majsec, Kristina ; Zheng, Qi ; Katagiri, Fumiaki

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, ostalo, znanstveni

Skup
ASPB Annual Plant Biology Meeting

Mjesto i datum
San Jose (CA), Sjedinjene Američke Države, 03.08.2019. - 07.08.2019

Vrsta sudjelovanja
Poster

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
CBP60 ; Arabidopsis ; plant immunity

Sažetak
We are interested in evoution of the plant immune signaling network and its components. CBP60 protein family in Arabidopsis consists of eight members: five prototypical (AtCBP60b-f) and three (AtCBP60a, AtCBP60g, AtSARD1) which are important immune regulators. AtCBP60a is a negative, while AtCBP60g and AtSARD1 are positive regulators of plant immunity. All three are involved in regulation of SA-signaling, and calmodulin (CaM) binding ability has been show to be essential for immune-related functions of AtCBP60a and AtCBP60g, while AtSARD1 lacks CaM-binding ability. To investigate evolution of protein families in land plants, we have created a protein database from 327 currently sequenced plant species, ranging from Liverwort to Eudicots. Subsequently we have established a pipeline for family member search and phylogenetic tree construction. We have applied the pipeline to the CBP60 family to infer family evolution. Our analysis shows that divergence of prototypical and immune-related clades occurred before divergence of ferns from the land plant lineage. Diversification of the three immune subfamilies within immune-related clade was completed before divergence of basal angiosperms. We have further analyzed all detected proteins by predicting their CaM-binding ability, binding site position and additional sequence features. CaM-binding ability seems to be present in majority of prototypical members. After divergence, this ability is gradually lost in members of immune-related subfamilies. We have identified two major drivers of this loss: (i) deletion of C-terminal CaM-binding domain and (ii) mutations at C-terminus that decrease alpha-helical propensity of the region. Surprisingly, CaM-binding ability seems not to be essential for immune-related function of CBP60 proteins in most Angiosperms, and could therefore be sacrificed while accumulating mutations in evasion of pathogen effectors.

Izvorni jezik
Engleski

Znanstvena područja
Biologija

POVEZANOST RADA