Changes in the levels of seven proteins involved in polypeptide folding and transport during endosperm development of two barley genotypes differing in storage protein localisation.
The Russian barley cultivar Nevsky lacks gamma 3 hordein and accumulates most of its hordein in the lumen of the endoplasmic reticulum and only a minor portion in the vacuole. In wild type barley and all other temperate cereals, storage proteins are deposited in the vacuole. F1 crosses revealed that the Nevsky phenotype is recessive; but the extent of hordein accumulation in the endoplasmic reticulum in F2 endosperm lacking gamma 3 hordein was very much less than in the Nevsky parent. In order to study the Nevsky endosperm phenotype we have measured the levels of seven proteins and two mRNAs involved in protein folding in the ER lumen or ER to Golgi transport during endosperm development. The protein levels were unaltered in Nevsky as compared to the wild-type variety Bomi. When the levels of these seven proteins were correlated with the rate of hordein accumulation, four of these (HSP70, PDI, Sar1p and Sec18p) were consistently up-regulated with hordein synthesis. Accumulation of hordein in the endoplasmic reticulum appears to be determined by the absence of gamma 3 hordein, or the product of a gene closely linked to it, plus one or more other recessive genes.
Møgelsvang
S
S
Department of Physiology, Carlsberg Laboratory, Valby, Denmark.
Simpson
D J
DJ
D000251:Adenosine Triphosphatases; D001692:Biological Transport; D015152:Blotting, Northern; D002135:Calcium-Binding Proteins / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D037282:Calreticulin; D005656:Fungal Proteins / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D019204:GTP-Binding Proteins / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D005838:Genotype; D006023:Glycoproteins / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D020662:Guanine Nucleotide Exchange Factors; D018840:HSP70 Heat-Shock Proteins / Q000096:biosynthesis / Q000235:genetics / Q000276:immunology; D001467:Hordeum / Q000254:growth & development* / Q000378:metabolism*; D008562:Membrane Glycoproteins / Q000276:immunology / Q000378:metabolism; D020559:Monomeric GTP-Binding Proteins; D010940:Plant Proteins / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D017510:Protein Folding; D012261:Ribonucleoproteins / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D029701:Saccharomyces cerevisiae Proteins; D012639:Seeds / Q000235:genetics / Q000254:growth & development / Q000378:metabolism; D033921:Vesicular Transport Proteins
D002135:Calcium-Binding Proteins; D037282:Calreticulin; D005656:Fungal Proteins; D006023:Glycoproteins; D020662:Guanine Nucleotide Exchange Factors; D018840:HSP70 Heat-Shock Proteins; D008562:Membrane Glycoproteins; D010940:Plant Proteins; D012261:Ribonucleoproteins; C071239:SEC12 protein, S cerevisiae; D029701:Saccharomyces cerevisiae Proteins; D033921:Vesicular Transport Proteins; D000251:Adenosine Triphosphatases; D019204:GTP-Binding Proteins; C064404:SEC18 protein, S cerevisiae; D020559:Monomeric GTP-Binding Proteins; C077395:SAR1 protein, S cerevisiae