AUTHOR=Li Wei , Li Xiaoxu , Chao Jiangtao , Zhang Zenglin , Wang Weifeng , Guo Yongfeng 

TITLE=NAC Family Transcription Factors in Tobacco and Their Potential Role in Regulating Leaf Senescence

JOURNAL=Frontiers in Plant Science

VOLUME=Volume 9 - 2018

YEAR=2018

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2018.01900

DOI=10.3389/fpls.2018.01900

ISSN=1664-462X

ABSTRACT=<p>The NAC family is one of the largest families of plant-specific transcription factors (TFs) and NAC proteins play important regulatory roles in a variety of developmental and stress response processes in plants. Members of the NAC family TFs have been shown to be important regulators of leaf senescence in a number of plant species. Here we report the identification of the NAC family in tobacco (<italic>Nicotiana tabacum</italic>) and characterization of the potential role of some of the tobacco NAC TFs in regulating leaf senescence. A total of 154 NAC genes (<italic>NtNACs</italic>) were identified and clustered together with the Arabidopsis NAC family into fifteen groups (a-o). Transcriptome data analysis followed by qRT-PCR validation showed that the majority of the senescence-up-regulated <italic>NtNAC</italic>s fall into subgroups NAC-b and f. A number of known senescence regulators from Arabidopsis also belong to these two subgroups. Among these senescence-up-regulated <italic>NtNACs</italic>, <italic>NtNAC080</italic>, a close homolog of AtNAP, is a positive regulator of leaf senescence. Overexpression of <italic>NtNAC080</italic> caused early senescence in Arabidopsis leaves and <italic>NtNAC080</italic> mutation induced by Cas9/gRNA in tobacco led to delayed leaf senescence.</p>