enod40, also known as early nodulin 40, is a gene found in flowering plants.

[1] There is some evidence that the non-coding characteristics of this gene are more widely conserved than the protein coding sequences.

[2] In soyabeans enod40 was found to be expressed during early stages of formation of nitrogen-fixing root nodules that are associated with symbiotic soil rhizobial bacteria.

[3][4] The gene is also active in roots containing fungi forming phosphate-acquiring arbuscular mycorrhiza.

[6] In the study of non-legume plants, the over-expression of ENOD40 in transgenic Arabidopsis lines was observed a reduction of cell expansion.