The Tomato Hybrid Proline-rich Protein regulates the abscission zone competence to respond to ethylene signals

Abstract

Abscission: Uncovering a master regulatory gene Investigations using tomato plant models provide insights into a key part of plants’ growth cycle. During healthy growth, plants deliberately drop unfertilized flowers and ripe fruit - a process called abscission. This process influences crop yields, yet the molecular mechanisms involved are not clear. Tomato plants provide a valuable model because they develop distinct abscission zones (AZ) at the stems (pedicels) attaching single flowers to the plant. Shimon Meir at the Agricultural Research Organization, The Volcani Center in Israel and co-workers uncovered the role of the tomato hybrid proline rich protein gene (THyPRP) in regulating the tomato flower AZ. Using a newly-developed microarray chip to monitor genes in the AZ, the team found that silencing THyPRP altered gene expression in the flower AZ, which in turn affected its competence to respond to ethylene signaling. They also identified several other proteins and signaling pathways involved in abscission.