Leaf development in Lolium temulentum: Gradients of RNA complement and plastid and non‐plastid transcripts

Gradients of gene expression in the developing fourth leaf of the grass Lolium temulentum L. strain Ba 3081 were investigated using cell‐free translation and Northern analysis of RNA extracted from succesive leaf segments. The transition from growth at the leaf base to photosynthesis in the blade was reflected in relative levels of transcripts from the plastid genome ( psb A, pet A and rbc L, encoding plastid polypeptides) and nuclear genome ( cab and PCR, encoding plastid polypeptides, and histone H3 and PAL encoding extra‐plastidic polypeptides). These data combined with information on polypeptide synthesis in vivo indicate that post‐transcriptional regulation plays an important part in controlling gene expression in this tissue.