COP9 Signalosome CSN4 and CSN5 Subunits Are Involved in Jasmonate-Dependent Defense Against Root-Knot Nematode in Tomato

• Published in: Frontiers in plant science 2019-10, Vol.10, p.1223-1223
• Main Authors: Shang, Yifen, Wang, Kaixin, Sun, Shuchang, Zhou, Jie, Yu, Jing-Quan
• Format: Article
• Language: English
• Subjects: basal defense; COP9 signalosome subunit 4 (CSN4); CSN5; jasmonic acid; Plant Science; root knot-nematode; tomato
• ISSN: 1664-462X; 1664-462X
• DOI: 10.3389/fpls.2019.01223

COP9 signalosome (CSN) is an evolutionarily conserved regulatory component of the ubiquitin/proteasome system that plays crucial roles in plant growth and stress tolerance; however, the mechanism of COP9-mediated resistance to root-knot nematodes (RKNs, e.g. Meloidogyne incognita ) is not fully understood in plants. In the present study, we found that RKN infection in the roots rapidly increases the transcript levels of CSN subunits 4 and 5 ( CSN4 and CSN5 ) and their protein accumulation in tomato ( Solanum lycopersicum ) plants. Suppression of CSN4 or CSN5 expression resulted in significantly increased number of egg masses and aggravated RKN-induced lipid peroxidation of cellular membrane but inhibited RKN-induced accumulation of CSN4 or CSN5 protein in tomato roots. Importantly, the RKN-induced accumulation of jasmonic acid (JA) and JA-isoleucine (JA-Ile), as well as the transcript levels of JA-related biosynthetic and signaling genes were compromised by CSN4 or CSN5 gene silencing. Moreover, protein–protein interaction assays demonstrated that CSN4 and CSN5B interact with the jasmonate ZIM domain 2 (JAZ2), which is the signaling component of the JA pathway. Silencing of CSN4 or CSN5 also compromises RKN-induced JAZ2 expression. Together, our findings indicate that CSN4 and CSN5 play critical roles in JA-dependent basal defense against RKN.