Abstract
A diversity of mRNAs containing only short open reading frames (sORF-RNAs; encoding less than 30 amino acids) have been shown to be induced in growth and differentiation processes. The early nodulin gene enod40, coding for a 0.7-kb sORF-RNA, is expressed in the nodule primordium developing in the root cortex of leguminous plants after infection by symbiotic bacteria. Ballistic microtargeting of this gene into Medicago roots induced division of cortical cells. Translation of two sORFs (I and II, 13 and 27 amino acids, respectively) present in the conserved 5' and 3' regions of enod40 was required for this biological activity. These sORFs may be translated in roots via a reinitiation mechanism. In vitro translation products starting from the ATG of sORF I were detectable by mutating enod40 to yield peptides larger than 38 amino acids. Deletion of a Medicago truncatula enod40 region between the sORFs, spanning a predicted RNA structure, did not affect their translation but resulted in significantly decreased biological activity. Our data reveal a complex regulation of enod40 action, pointing to a role of sORF-encoded peptides and structured RNA signals in developmental processes involving sORF-RNAs.
Publication types
-
Research Support, Non-U.S. Gov't
MeSH terms
-
Base Sequence
-
Biolistics
-
Cell Division
-
Gene Expression Regulation, Developmental
-
Gene Expression Regulation, Plant*
-
Gene Targeting
-
Genes, Reporter / genetics
-
Immunohistochemistry
-
Medicago sativa / genetics*
-
Medicago sativa / growth & development
-
Medicago sativa / metabolism
-
Molecular Sequence Data
-
Mutation / genetics
-
Nucleic Acid Conformation
-
Open Reading Frames / genetics
-
Peptides / chemistry
-
Peptides / genetics
-
Peptides / metabolism
-
Plant Growth Regulators / biosynthesis
-
Plant Growth Regulators / chemistry
-
Plant Growth Regulators / genetics
-
Plant Growth Regulators / metabolism
-
Plant Proteins / biosynthesis*
-
Plant Proteins / chemistry
-
Plant Proteins / genetics
-
Plant Proteins / metabolism
-
Plant Roots / genetics
-
Plant Roots / growth & development*
-
Plant Roots / metabolism
-
Protein Biosynthesis / genetics*
-
RNA, Long Noncoding
-
RNA, Plant / chemistry
-
RNA, Plant / genetics*
-
RNA, Plant / metabolism
-
RNA, Untranslated / chemistry
-
RNA, Untranslated / genetics
-
RNA, Untranslated / metabolism*
-
Recombinant Fusion Proteins / biosynthesis
Substances
-
ENOD40 RNA
-
Peptides
-
Plant Growth Regulators
-
Plant Proteins
-
RNA, Long Noncoding
-
RNA, Plant
-
RNA, Untranslated
-
Recombinant Fusion Proteins