Review: Losing JAZ4 for growth and defense.

JAZ proteins are involved in the regulation of the jasmonate signaling pathway, which is responsible for various physiological processes, such as defense response, adaptation to abiotic stress, growth, and development in Arabidopsis. The conserved domains of JAZ proteins can serve as binding sites for a broad array of regulatory proteins and the diversity of these protein-protein pairings result in a variety of functional outcomes. Plant growth and defense are two physiological processes that can conflict with each other, resulting in undesirable plant trade-offs.

Spatiotemporal regulation of JAZ4 expression and splicing contribute to ethylene- and auxin-mediated responses in Arabidopsis roots.

Jasmonic acid (JA) signaling controls several processes related to plant growth, development, and defense, which are modulated by the transcription regulator and receptor JASMONATE-ZIM DOMAIN (JAZ) proteins. We recently discovered that a member of the JAZ family, JAZ4, has a prominent function in canonical JA signaling as well as other mechanisms. Here, we discovered the existence of two naturally occurring splice variants (SVs) of JAZ4 in planta, JAZ4.

JAZ4 is involved in plant defense, growth, and development in Arabidopsis.

Jasmonate zim-domain (JAZ) proteins comprise a family of transcriptional repressors that modulate jasmonate (JA) responses. JAZ proteins form a co-receptor complex with the F-box protein coronatine insensitive1 (COI1) that recognizes both jasmonoyl-l-isoleucine (JA-Ile) and the bacterial-produced phytotoxin coronatine (COR). Although several JAZ family members have been placed in this pathway, the role of JAZ4 in this model remains elusive.

Importin-β Directly Regulates the Motor Activity and Turnover of a Kinesin-4.

Spatiotemporal regulation of kinesins is essential for microtubule-dependent intracellular transport. In plants, cell wall deposition depends on the FRA1 kinesin, whose abundance and motility are tightly controlled to match cellular growth rate. Here, we show that an importin-β, IMB4, regulates FRA1 activity in a developmental manner.

The kinesin-4, FRA1, requires a high level of processive motility to function correctly.

Processivity is important for kinesins that mediate intracellular transport. Structure-function analyses of N-terminal kinesins (i.e.