AUTHOR=Li Pengfeng , Du Runjie , Li Zhaopeng , Chen Zhuo , Li Jiana , Du Hai 

TITLE=An integrated nitrogen utilization gene network and transcriptome analysis reveal candidate genes in response to nitrogen deficiency in Brassica napus

JOURNAL=Frontiers in Plant Science

VOLUME=14

YEAR=2023

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2023.1187552

DOI=10.3389/fpls.2023.1187552

ISSN=1664-462X

ABSTRACT=<p>Nitrogen (N) is an essential factor for crop yield. Here, we characterized 605 genes from 25 gene families that form the complex gene networks of N utilization pathway in <italic>Brassica napus</italic>. We found unequal gene distribution between the A<sub>n</sub>- and C<sub>n</sub>-sub-genomes, and that genes derived from <italic>Brassica rapa</italic> were more retained. Transcriptome analysis indicated that N utilization pathway gene activity shifted in a spatio-temporal manner in <italic>B. napus</italic>. A low N (LN) stress RNA-seq of <italic>B. napus</italic> seedling leaves and roots was generated, which proved that most N utilization related genes were sensitive to LN stress, thereby forming co-expression network modules. Nine candidate genes in N utilization pathway were confirmed to be significantly induced under N deficiency conditions in <italic>B. napus</italic> roots, indicating their potential roles in LN stress response process. Analyses of 22 representative species confirmed that the N utilization gene networks were widely present in plants ranging from Chlorophyta to angiosperms with a rapid expansion trend. Consistent with <italic>B. napus</italic>, the genes in this pathway commonly showed a wide and conserved expression profile in response to N stress in other plants. The network, genes, and gene-regulatory modules identified here represent resources that may enhance the N utilization efficiency or the LN tolerance of <italic>B. napus</italic>.</p>