Senescence-Associated Vacuoles, a Specific Lytic Compartment for Degradation of Chloroplast Proteins?

Plants

Cristian A. Carrión¹  Dana E. Martínez¹  M. Lorenza Costa¹ 

[1] Instituto de Fisiología Vegetal (INFIVE, CONICET-UNLP), cc327, La Plata 1900, Argentina;

关键词: senescence-associated vacuoles;    leaf senescence;    chloroplast degradation;    proteases;    Rubisco;    SAG12;   

DOI  :  10.3390/plants3040498

来源: mdpi

【 摘 要 】

Degradation of chloroplasts and chloroplast components is a distinctive feature of leaf senescence. In spite of its importance in the nutrient economy of plants, knowledge about the mechanism(s) involved in the breakdown of chloroplast proteins is incomplete. A novel class of vacuoles, “senescence-associated vacuoles” (SAVs), characterized by intense proteolytic activity appear during senescence in chloroplast-containing cells of leaves. Since SAVs contain some chloroplast proteins, they are candidate organelles to participate in chloroplast breakdown. In this review we discuss the characteristics of SAVs, and their possible involvement in the degradation of Rubisco, the most abundant chloroplast protein. Finally, SAVs are compared with other extra-plastidial protein degradation pathways operating in senescing leaves.

【 授权许可】

CC BY   
© 2014 by the authors; licensee MDPI, Basel, Switzerland.