SNOWY COTYLEDON 2 Promotes Chloroplast Development and Has a Role in Leaf Variegation in Both Lotus japonicus and Arabidopsis thaliana

TY - JOUR

T1 - SNOWY COTYLEDON 2 Promotes Chloroplast Development and Has a Role in Leaf Variegation in Both Lotus japonicus and Arabidopsis thaliana

AU - Zagari, Nicola

AU - Sandoval-Ibanez, Omar

AU - Sandal, Niels

AU - Su, Junyi

AU - Rodriguez-Conception, Manuel

AU - Stougaard, Jens

AU - Pribil, Mathias

AU - Leister, Dario

AU - Pulido, Pablo

PY - 2017

Y1 - 2017

N2 - Plants contain various factors that transiently interact with subunits or intermediates of the thylakoid multiprotein complexes, promoting their stable association and integration. Hence, assembly factors are essential for chloroplast development and the transition from heterotrophic to phototrophic growth. Snowy cotyledon 2 (SCO2) is a DNAJ-like protein involved in thylakoid membrane biogenesis and interacts with the light-harvesting chlorophyll-binding protein LHCB1. In Arabidopsis thaliana, SCO2 function was previously reported to be restricted to cotyledons. Here we show that disruption of SCO2 in Lotus japonicus results not only in paler cotyledons but also in variegated true leaves. Furthermore, smaller and pale-green true leaves can also be observed in A. thaliana sco2 (atsco2) mutants under short-day conditions. In both species, SCO2 is required for proper accumulation of PSII–LHCII complexes. In contrast to other variegated mutants, inhibition of chloroplastic translation strongly affects L. japonicus sco2 mutant development and fails to suppress their variegated phenotype. Moreover, inactivation of the suppressor of variegation AtClpR1 in the atsco2 background results in an additive double-mutant phenotype with variegated true leaves. Taken together, our results indicate that SCO2 plays a distinct role in PSII assembly or repair and constitutes a novel factor involved in leaf variegation.

AB - Plants contain various factors that transiently interact with subunits or intermediates of the thylakoid multiprotein complexes, promoting their stable association and integration. Hence, assembly factors are essential for chloroplast development and the transition from heterotrophic to phototrophic growth. Snowy cotyledon 2 (SCO2) is a DNAJ-like protein involved in thylakoid membrane biogenesis and interacts with the light-harvesting chlorophyll-binding protein LHCB1. In Arabidopsis thaliana, SCO2 function was previously reported to be restricted to cotyledons. Here we show that disruption of SCO2 in Lotus japonicus results not only in paler cotyledons but also in variegated true leaves. Furthermore, smaller and pale-green true leaves can also be observed in A. thaliana sco2 (atsco2) mutants under short-day conditions. In both species, SCO2 is required for proper accumulation of PSII–LHCII complexes. In contrast to other variegated mutants, inhibition of chloroplastic translation strongly affects L. japonicus sco2 mutant development and fails to suppress their variegated phenotype. Moreover, inactivation of the suppressor of variegation AtClpR1 in the atsco2 background results in an additive double-mutant phenotype with variegated true leaves. Taken together, our results indicate that SCO2 plays a distinct role in PSII assembly or repair and constitutes a novel factor involved in leaf variegation.

KW - DNAJ-like

KW - SCO2

KW - assembly factor

KW - chloroplast development

KW - photosynthesis

KW - variegation

UR - http://www.scopus.com/inward/record.url?scp=85018392212&partnerID=8YFLogxK

U2 - 10.1016/j.molp.2017.02.009

DO - 10.1016/j.molp.2017.02.009

M3 - Journal article

C2 - 28286296

SN - 1674-2052

VL - 10

SP - 721

EP - 734

JO - Molecular Plant

JF - Molecular Plant

IS - 5

ER -