Maize B Chromosome Affects the Transcription of A chromosome

The B chromosome of maize (Zea mays L.) is widely believed to not have functional genes. However, its existence may be able to influence the expression of genes from the A genome. Previous studies have also suggested that B chromosomes might contain regions homologous to A chromosome sequences. A team of researchers, led by Wei Huang from the China Agricultural University, further studied the maize B chromosome.

Their results suggest that maize B chromosome influences the A-genome transcription, and this influence strengthens as the copy number of B chromosome increases. One hundred thirty differently expressed genes were detected between lines with and without B chromosome lines. These differentially expressed genes were mainly involved in cell metabolism and nucleotide binding. B-located transcriptionally active genes also showed high similarity to their A-genome homologues. 

These results shed light on the genome structure and evolution of the maize B chromosome.

For more information, read the article on BMC Plant Biology.