Expression of the triose phosphate translocator gene from potato is light dependent and restricted to green tissues.
The export of primary photosynthesis products from chloroplasts into the cytoplasm is mediated by the triose phosphate translocator. The transporter is an integral membrane protein localized at the inner envelope of chloroplasts. In order to study the expression of the major chloroplast envelope protein gene E29, which is assumed to function as the translocator, we have isolated corresponding cDNA clones from potato. A full-length clone was sequenced and shown to be highly homologous to the E29 gene from spinach. Expression on the RNA level is restricted to green tissues, is light dependent and cannot be induced by sucrose in darkness. The presence of a single-copy gene argues for the existence of different translocator systems responsible for import and export of carbohydrates in chloroplasts and amyloplasts.
Schulz
B
B
Institut für Genbiologische Forschung, Berlin, Germany.
Frommer
W B
WB
Flügge
U I
UI
Hummel
S
S
Fischer
K
K
Willmitzer
L
L
D000595:Amino Acid Sequence; D060365:Chloroplast Proteins; D003001:Cloning, Molecular; D015870:Gene Expression; D008027:Light; D008565:Membrane Proteins / Q000737:chemistry / Q000235:genetics*; D026901:Membrane Transport Proteins; D008969:Molecular Sequence Data; D009928:Organ Specificity; D010940:Plant Proteins / Q000737:chemistry / Q000235:genetics*; D012333:RNA, Messenger / Q000096:biosynthesis; D011198:Solanum tuberosum / Q000737:chemistry / Q000235:genetics*; D013045:Species Specificity
D060365:Chloroplast Proteins; D008565:Membrane Proteins; D026901:Membrane Transport Proteins; D010940:Plant Proteins; D012333:RNA, Messenger