Search

Auxin response factors (ARFs) mediate auxin response gene transcription by directly binding with AuxREs. However, whether ARF family genes involved in anthocyanin accumulation in apple is largely unexplored. In this study, thirty-three MdARF family members were identified in the apple (Malus × domestica) genome (HFTH1 Whole Genome v1.0) based on the sequence similarity with ARF family members of Arabidopsis. Phylogenetic analysis revealed that thirty-three MdARF members were clustered into Class I, Class II and Class III. Functional domain analysis showed that MdARF proteins have some typical domains such as B3-like DNA-binding domain and Auxin_resp domain, as well as motif III and motif IV. Chromosome localisation analysis demonstrated that apple ARF members were widely distributed in the genome. Among these MdARF genes, MdARF2 was significantly correlated with anthocyanin variation according to extracting expression profiles from published RNA-seq data. Further functional identification in apple calli suggested that MdARF2 functions as a transcriptional repressor of anthocyanin biosynthesis. These findings provide evidence that MdARF family members play a role in the regulation of anthocyanin accumulation in apple. [ABSTRACT FROM AUTHOR]

Apple, one of the most common fruits consumed worldwide, has a high economic value. Vacuoles are membrane-bound organelles in plant cells that perform many important functions. An increasing number of studies have reported a variety of proteins in a vacuole, with crucial functions in the transport, storage and metabolism of energy and substances. Here, we successfully extracted the vacuoles and vacuolar proteins from the ‘Orin’ apple fruit calli. We collected intact vacuoles with a density of 100/mm2 by mild osmotic lysis and Ficoll density gradient centrifugation. The result of SDS-PAGE showed that lots of vacuolar proteins were isolated and enriched from vacuole samples, and western blotting showed that the purity of the vacuolar protein was high. Furthermore, we showed GO enrichment and KEGG enrichment of isolated vacuolar proteins and selected 41 vacuolar proteins with known functions and 10 vacuolar proteins with unknown functions for functional annotation from the mass spectrometry analysis. This approach for vacuole isolation and vacuolar protein identification will provide a theoretical basis for further study of the function of vacuoles and vacuolar proteins. [ABSTRACT FROM AUTHOR]