Native and Artificial Reticuloplasmins Co-Accumulate in Distinct Domains of the Endoplasmic Reticulum and in Post-Endoplasmic Reticulum Compartments1
AUTOR(ES)
Torres, Esperanza
FONTE
American Society of Plant Physiologists
RESUMO
We compared the subcellular distribution of native and artificial reticuloplasmins in endosperm, callus, and leaf tissues of transgenic rice (Oryza sativa) to determine the distribution of these proteins among endoplasmic reticulum (ER) and post-ER compartments. The native reticuloplasmin was calreticulin. The artificial reticuloplasmin was a recombinant single-chain antibody (scFv), expressed with an N-terminal signal peptide and the C-terminal KDEL sequence for retrieval to the ER (scFvT84.66-KDEL). We found that both molecules were distributed in the same manner. In endosperm, each accumulated in ER-derived prolamine protein bodies, but also in glutelin protein storage vacuoles, even though glutelins are known to pass through the Golgi apparatus en route to these organelles. This finding may suggest that similar mechanisms are involved in the sorting of reticuloplasmins and rice seed storage proteins. However, the presence of reticuloplasmins in protein storage vacuoles could also be due to simple dispersal into these compartments during protein storage vacuole biogenesis, before glutelin deposition. In callus and leaf mesophyll cells, both reticuloplasmins accumulated in ribosome-coated vesicles probably derived directly from the rough ER.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=129289Documentos Relacionados
- Unexpected Deposition Patterns of Recombinant Proteins in Post-Endoplasmic Reticulum Compartments of Wheat Endosperm1
- Overexpression of PCSK9 accelerates the degradation of the LDLR in a post-endoplasmic reticulum compartment
- Regulation of PACE propeptide-processing activity: requirement for a post-endoplasmic reticulum compartment and autoproteolytic activation.
- Golgi Apparatus Immunolocalization of Endomannosidase Suggests Post-Endoplasmic Reticulum Glucose Trimming: Implications for Quality Control
- Diversity and Formation of Endoplasmic Reticulum-Derived Compartments in Plants. Are These Compartments Specific to Plant Cells?1