Description of Flower Biology of Under-Exploited Species, <i>Zingiber barbatum</i>(Wall.) from Myanmar

Characterization of the reproductive morphology in genus Zingiber is still relevant on classical taxonomic studies because most of the species are phenotypically similar and difficult to distinguish in the absence of the flowering stage. Reports mainly derived based on the herbarium collections are insufficient for the detailed morphological review. Zingiber barbatum (Wall.) belongs to the genus Zingiber and has been neglected for a long time. Existed intraspecific morphological and genetic variations also intricate the description of this species. The objective of this study was to characterize the reproductive morphology of under-exploited Z. barbatum species. The study was done based on the traditional description of morphology and habit of inflorescence and flowers, with a recording of minimum quantitative and qualitative parameters and phenological observation regarding inflorescence life span and duration of blossom. Assessment of reproductive morphology displayed phenotypic variations regarding inflorescences habit during the growth stage and morphological features of the flower. Perhaps, an existed variation was driven by eco-geographical factors resulting in reproductive isolation due to which genetic divergence might occur. The taxonomic affiliation of Z. barbatum based on inflorescence habit has been confirmed. This is the first comprehensive report regarding flower biology on Z. barbatum.

Assembly of JAZ–JAZ and JAZ–NINJA complexes in jasmonate signaling

Jasmonates(JAs)are plant hormones with crucial roles in development and stress resilience.They activate MYC transcription factors by mediating the proteolysis of MYC inhibitors called JAZ proteins.In the absence of JA,JAZ proteins bind and inhibit MYC through the assembly of MYC–JAZ–Novel Interactor of JAZ(NINJA)–TPL repressor complexes.However,JAZ and NINJA are predicted to be largely intrinsically unstructured,which has precluded their experimental structure determination.Through a combination of biochemical,mutational,and biophysical analyses and AlphaFold-derived ColabFold modeling,we characterized JAZ–JAZ and JAZ–NINJA interactions and generated models with detailed,high-confidence domain interfaces.We demonstrate that JAZ,NINJA,and MYC interface domains are dynamic in isolation and become stabilized in a stepwise order upon complex assembly.By contrast,most JAZ and NINJA regions outside of the interfaces remain highly dynamic and cannot be modeled in a single conformation.Our data indicate that the small JAZ Zinc finger expressed in Inflorescence Meristem(ZIM)motif mediates JAZ–JAZ and JAZ–NINJA interactions through separate surfaces,and our data further suggest that NINJA modulates JAZ dimerization.This study advances our understanding of JA signaling by providing insights into the dynamics,interactions,and structure of the JAZ–NINJA core of the JA repressor complex.