The massive synthesis of seed storage proteins (SSPs) in the relatively short time of seed formation challenges the endoplasmic reticulum (ER) folding machinery, which involves numerous chaperones, enzymes and lectins as well as signal transduction pathways that regulate the machinery activities depending on the ER workload and the folding requirements of the specific proteins synthesized, and may also respond to biotic and abiotic stresses that alter ER proteostasis and could therefore disturb storage protein accumulation in natural environments. By a cell biology point of view, storage proteins can be grouped into two large classes: the albumins and globulins, present in all plants, which accumulate in vacuoles, and the prolamins, which do not traffic out of the ER and accumulate within it as unique large insoluble polymers, giving rise to storage organelles called Protein Bodies (PB). Prolamins are specific of cereals and other grasses, where they constitute the major storage protein fraction. Using one model globulin and a number of wild type and engineered maize prolamins individually expressed in transgenic A. thaliana, we are attempting to finely define quantitative and qualitative variability in the extent with which storage proteins having markedly different structures and final destinies challenge the ER machinery, also under environmental stress.
PROTEIN-SPECIFIC CHALLENGE TO THE ER QUALITY CONTROL
Lucrezia LUCIANI;Emanuela PEDRAZZINI
Ultimo
2024
Abstract
The massive synthesis of seed storage proteins (SSPs) in the relatively short time of seed formation challenges the endoplasmic reticulum (ER) folding machinery, which involves numerous chaperones, enzymes and lectins as well as signal transduction pathways that regulate the machinery activities depending on the ER workload and the folding requirements of the specific proteins synthesized, and may also respond to biotic and abiotic stresses that alter ER proteostasis and could therefore disturb storage protein accumulation in natural environments. By a cell biology point of view, storage proteins can be grouped into two large classes: the albumins and globulins, present in all plants, which accumulate in vacuoles, and the prolamins, which do not traffic out of the ER and accumulate within it as unique large insoluble polymers, giving rise to storage organelles called Protein Bodies (PB). Prolamins are specific of cereals and other grasses, where they constitute the major storage protein fraction. Using one model globulin and a number of wild type and engineered maize prolamins individually expressed in transgenic A. thaliana, we are attempting to finely define quantitative and qualitative variability in the extent with which storage proteins having markedly different structures and final destinies challenge the ER machinery, also under environmental stress.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.