Seasonal nitrogen (N) remobilization is an extensive process in perennial plants requiring
communication between N sinks and storage tissues (sources). These plants coordinate
changes between expanding buds/shoots and bark to guarantee N storage resources
during the dormant season and N utilization during the growth phase. Based on seasonal
nitrogen cycling in Populus, Li et al. (2020) have proposed a novel model using
knockdown of bark storage proteins (BSPs) transgenic plants, where auxin production
leads to N mobilization from BSPs to expanding buds. This represents a significant step
forward in understanding the role of BSP during seasonal plant growth and how N
remobilization in trees is regulated.
