Host metabolic interaction and perspectives in phytoplasma research

Phytoplasmas are plant pathogenic bacteria that have large economic impacts on crops and landscape plants. Knowledge of their biology is limited also because they are still not easily cultured in media. It is still a mystery how phytoplasmas use the sugar-rich phloem sap and how they interact with the hosts. It is agriculturally important to identify the factors involved in their pathogenicity and to discover effective measures to control phytoplasma-associated diseases. The knowledge about host-pathogen interaction during the infection process can help to elucidate the processes leading to symptom expression. Transcriptomics studies paved the way for analysing the gene expression pattern in phytoplasma-infected plants and revealed the up-regulation of genes responsible for hormonal balance, transcription factors, and signalling. Recent studies have identified potential virulence factors that induce some of the typical phytoplasma disease symptoms and have started the annotation of their genomes having unique reductive evolution features. The novel manipulation tool represented by the potential of the synthetic biology can be helpful for its potential application in studying efficient management strategies to reduce the agricultural impact of the diseases associated with the phytoplasma presence.