MCM2 partial silencing inhibits apical dominance and promotes chlorophyll pigmentation in tomato

Background: We have previously combined loss- and gain-of-function approaches to investigate the function of Arabidopsis minichromosome maintenance (MCM) protein subunit 2 (MCM2). However MCM2 loss of function leads to the death of embryos, thus precluding the analysis of homozygous MCM2 mutants. Methods: : To further understand the function of MCM2, we generated transgenic tomato plants via RNA interference silencing. And microarray slide hybridization was used to compare gene expression level between LeMCM2 -silenced lines and wild-type plants. Results: : We obtained 4 LeMCM2 -silenced lines. The expression level in LeMCM2 -silenced lines was 20-80% of that of wild-type. And LeMCM2 -silenced lines display loss of apical dominance, enhanced chlorophyll accumulation and reduced leaf cell endoduplication. In addition, the expression levels of genes involved in DNA replication was altered in LeMCM2 -silenced lines significantly. Conclusion: In general, the data described here provided additional evidence for the relationship between genes involved in DNA replication and apical dominance and chlorophyll pigmentation.