Sequence-specific interaction between S1F, a spinach nuclear factor, and a negative cis-element conserved in plastid-related genes.

D X Zhou; Y F Li; M Rocipon; R Mache

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PubMed · 1429696

Sequence-specific interaction between S1F, a spinach nuclear factor, and a negative cis-element conserved in plastid-related genes.

D X Zhou·Y F Li·M Rocipon·R Mache

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Abstract

The nuclear gene rps1 coding for the spinach plastid ribosomal protein CS1 exhibits both a constitutive and leaf-specific expression pattern. In contrast to other chloroplast-related genes like rbcS and cab, the leaf induction of rps1 expression is light-independent. These unique features of rps1 expression provide good models to study the mechanisms regulating plastid development and differentiation in higher plants. We report on the identification of a spinach leaf nuclear factor, designated S1F, interacting with the rps1 promoter. The S1F binding site is conserved in the promoter region of many plastid-related genes, including rbcS, cab, and rpl21. A binding activity similar to S1F was detected in nuclear extract from dark-grown de-differentiated soybean suspension cells. Through site-specific mutagenesis and transient expression in soybean cell protoplasts, we show that the S1F binding site is a negative element down-regulating the promoter activity of rps1. A ligated tetramer of S1F site was able to repress activity of the cauliflower mosaic virus 35 S promoter extending the negative function of the S1F binding site on promoter activity.

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Base Sequence Biological Evolution Cell Nucleus Gene Expression Molecular Sequence Data Mutagenesis, Site-Directed Nuclear Proteins Plant Proteins Plants Plasmids Polymerase Chain Reaction Promoter Regions, Genetic Restriction Mapping Ribosomal Proteins Sequence Homology, Nucleic Acid Glycine max Transcription, Genetic Comparative Study Journal Article

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D X Zhou, Y F Li, M Rocipon, R Mache. 1992-11-25. Sequence-specific interaction between S1F, a spinach nuclear factor, and a negative cis-element conserved in plastid-related genes.. https://pubmed.ncbi.nlm.nih.gov/1429696/

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