Ectopic Expression of Pineapple Actin-Related Protein 6 (AcARP6) Regulates Flowering and Stress Responses in Arabidopsis

SWR1 chromatin remodeling complex (SWR1-C) plays a crucial role in gene regulation during growth and development of eukaryotes. ACTIN-RELATED PROTEIN 6 (ARP6), an essential subunit of SWR1-C, is implicated in flowering and stress response. However, the functions of pineapple ARP6 have not been investigated, which limits its potential use in molecular breeding. Here, pineapple ARP6 is functionally characterized and its role in flowering, salt stress, drought, nutrient deficiency and immunity is verified. Phylogenetic analysis showed that AcARP6 is homologous to ARP6 of rice and Arabidopsis . Expression analysis revealed that AcARP6 gets induced by salt, osmotic and nutrient deficiency. Additionally, ectopic expression of AcARP6 in Arabidopsis delayed flowering and increased tolerance to salinity, drought and nutrient deficiency, but displayed sensitivity against Sclerotinia sclerotiorum infection. Furthermore, AcARP6 complemented the phenotypic defects of the arp6 mutation in Arabidopsis . These results provide evidence for the involvement of AcARP6 in multiple stress responses and advocate that AcARP6 could be used as a potential candidate gene for improving tolerance against abiotic stresses.