AUTHOR=Chen Yuxi , Zhou Rijin , Hu Qiong , Wei Wenliang , Liu Jia 

TITLE=Conservation and Divergence of the CONSTANS-Like (COL) Genes Related to Flowering and Circadian Rhythm in Brassica napus

JOURNAL=Frontiers in Plant Science

VOLUME=12

YEAR=2021

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2021.760379

DOI=10.3389/fpls.2021.760379

ISSN=1664-462X

ABSTRACT=<p>The <italic>CONSTANS-LIKE (COL)</italic> genes are important signaling component in the photoperiod pathway and flowering regulation pathway. However, people still know little about their role in <italic>Brassica napus</italic>. To achieve a better understanding of the members of the <italic>BnaCOL</italic> gene family, reveal their evolutionary relationship and related functions involved in photoperiod regulation, we systematically analyzed the <italic>BnaCOL</italic> family members in <italic>B. napus</italic> genome. A total of 33 <italic>BnaCOL</italic> genes distributed unevenly on 16 chromosomes were identified in <italic>B. napus</italic> and could be classified into three subfamilies. The same subfamilies have relatively conservative gene structures, three-dimensional protein structures and promoter motifs such as light-responsive <italic>cis</italic>-elements. The collinearity analysis detected 37 pairs of repetitive genes in <italic>B. napus</italic> genome. A 67.7% of the <italic>BnaCOL</italic> genes were lost after <italic>B. napus</italic> genome polyploidization. In addition, the <italic>BnaCOL</italic> genes showed different tissue-specific expression patterns. A 81.8% of the <italic>BnaCOL</italic> genes were mainly expressed in leaves, indicating that they may play a conservative role in leaves. Subsequently, we tested the circadian expression profiles of nine homologous genes that regulate flowering in <italic>Arabidopsis</italic>. Most <italic>BnaCOL</italic> genes exhibit several types of circadian rhythms, indicating that these <italic>BnaCOL</italic> genes are involved in the photoperiod pathway. As such, our research has laid the foundation for understanding the exact role of the <italic>BnaCOL</italic> family in the growth and development of rapeseed, especially in flowering.</p>