TIP, an integral membrane protein of the protein-storage vacuoles of the soybean cotyledon undergoes developmentally regulated membrane accumulation and removal

Planta ◽  
1991 ◽  
Vol 184 (1) ◽  
Author(s):  
DaineL. Melroy ◽  
EliotM. Herman
1995 ◽  
Vol 108 (1) ◽  
pp. 299-310 ◽  
Author(s):  
B. Hoh ◽  
G. Hinz ◽  
B.K. Jeong ◽  
D.G. Robinson

We have investigated the formation of protein storage vacuoles in peas (Pisum sativum L.) in order to determine whether this organelle arises de novo during cotyledon development. A comparison of different stages in cotyledon development indicates that soluble protease activities decline and the amounts of storage proteins and the integral membrane protein of the protein body, alpha-TIP, increase during seed maturation. On linear sucrose density gradients we have been able to distinguish between two separate vesicle populations: one enriched in alpha-TIP, and one in TIP-Ma 27, a membrane protein characteristic of vegetative vacuoles. Both vesicle populations possess, however, PPase and V-ATPase activities. Conventionally fixed cotyledonary tissue at an intermediate stage in cotyledon development reveals the presence of a complex tubular-cisternal membrane system that seems to surround the pre-existing vacuoles. The latter gradually become compressed as a result of dilation of the former membrane system. This was confirmed immunocytochemically with the TIP-Ma 27 antiserum. Deposits of the storage proteins vicilin and legumin in the lumen, and the presence of alpha-TIP in the membranes of the expanding membrane system provide evidence of its identity as a precursor to the protein storage vacuole.


2001 ◽  
Vol 13 (10) ◽  
pp. 2361-2372 ◽  
Author(s):  
Naoto Mitsuhashi ◽  
Yasuko Hayashi ◽  
Yasuko Koumoto ◽  
Tomoo Shimada ◽  
Tomoko Fukasawa-Akada ◽  
...  

2001 ◽  
Vol 13 (10) ◽  
pp. 2361
Author(s):  
Naoto Mitsuhashi ◽  
Yasuko Hayashi ◽  
Yasuko Koumoto ◽  
Tomoo Shimada ◽  
Tomoko Fukasawa-Akada ◽  
...  

2019 ◽  
Vol 71 (3) ◽  
pp. 808-822 ◽  
Author(s):  
Zhongyan Wei ◽  
Tian Pan ◽  
Yuyang Zhao ◽  
Bohong Su ◽  
Yulong Ren ◽  
...  

Abstract Storage protein is the most abundant nutritional component in soybean seed. Morphology-based evidence has verified that storage proteins are initially synthesized on the endoplasmic reticulum, and then follow the Golgi-mediated pathway to the protein storage vacuole. However, the molecular mechanisms of storage protein trafficking in soybean remain unknown. Here, we clone the soybean homologs of Rab5 and its guanine nucleotide exchange factor (GEF) VPS9. GEF activity combined with yeast two-hybrid assays demonstrated that GmVPS9a2 might specifically act as the GEF of the canonical Rab5, while GmVPS9b functions as a common activator for all Rab5s. Subcellular localization experiments showed that GmRab5a was dually localized to the trans-Golgi network and pre-vacuolar compartments in developing soybean cotyledon cells. Expression of a dominant negative variant of Rab5a, or RNAi of either Rab5a or GmVPS9s, significantly disrupted trafficking of mRFP–CT10, a cargo marker for storage protein sorting, to protein storage vacuoles in maturing soybean cotyledons. Together, our results systematically revealed the important role of GmRab5a and its GEFs in storage protein trafficking, and verified the transient expression system as an efficient approach for elucidating storage protein trafficking mechanisms in seed.


2000 ◽  
Vol 150 (4) ◽  
pp. 755-770 ◽  
Author(s):  
Liwen Jiang ◽  
Thomas E. Phillips ◽  
Sally W. Rogers ◽  
John C. Rogers

We identify new organelles associated with the vacuolar system in plant cells. These organelles are defined biochemically by their internal content of three integral membrane proteins: a chimeric reporter protein that moves there directly from the ER; a specific tonoplast intrinsic protein; and a novel receptor-like RING-H2 protein that traffics through the Golgi apparatus. Highly conserved homologues of the latter are expressed in animal cells. In a developmentally regulated manner, the organelles are taken up into vacuoles where, in seed protein storage vacuoles, they form a membrane-containing crystalloid. The uptake and preservation of the contents of these organelles in vacuoles represents a unique mechanism for compartmentalization of protein and lipid for storage.


Sign in / Sign up

Export Citation Format

Share Document