The carrot secreted glycoprotein gene EP1 is expressed in the epidermis and has sequence homology to Brassica S-locus glycoproteins

Non-embryogenic carrot suspension cells secrete the EP1 glycoprotein. A cDNA clone encoding EP1 was isolated and sequenced. The EP1 sequence revealed a region of homology with Brassica S-locus glycoprotein genes, an Arabidopsis S-like gene and putative S-like receptor protein kinases from maize and Arabidopsis. EP1 gene expression, analysed by in situ mRNA localization, was detected in cells located at the surface of the seedling: in the epidermis of the root, the hypocotyl and the cotyledons, in the root cap, and in a crescent of cells in the apical dome of the shoot. In developing seeds, expression was most pronounced in both the inner and outer integument epidermis.     

Impaired growth on glucose of a pyruvate dehydrogenase-negative mutant of Kluyveromyces lactis is due to a limitation in mitochondrial acetyl-coenzyme A uptake

A Kluyveromyces lactis mutant with a disruption in the KlPDA1 gene, encoding the E1 alpha subunit of the pyruvate dehydrogenase complex, exhibited a four-fold reduced specific growth rate on glucose in minimal medium. Growth of the Klpda1 mutant on glucose in complex medium was not affected. Its growth on defined media could be restored by adding amino acids that require mitochondrial acetyl-CoA for their biosynthesis as nitrogen sources. This, together with the observation that low-concentrations of L-carnitine also restored growth on glucose, indicates that the slow-growth phenotype of the Klpda1 mutant is due to a limited capacity of the mitochondria for import of cytosolic acetyl-CoA.