Organ-specific expression of three leaf/stem specific cDNAs from potato is regulated by light and correlated with chloroplast development

A cDNA library established from polyA+ RNA of leaves from potato (Solanum tuberosum) was analysed for sequences specifically present in leaves. Three cDNA-clones, one of which is the small subunit of Ribulose-1,5-bis-phosphate carboxylase (ss Rubisco), were obtained via differential screening using RNA from leaves, roots and tubers. Northern and RNA dot blot analysis demonstrate that the expression of these clones is higher by at least a factor of 100–500 in leaves as compared to roots and tubers. Genomic blot analysis shows that all three cDNA clones are encoded by small, multigene families.