Non-TZF Transcriptional Activator AtC3H12 Negatively Affects Seed Germination and Seedling Development in Arabidopsis

Abstract

CCCH zinc finger proteins are a large protein family and are classified as either tandem CCCH zinc finger (TZF) or non-TZF proteins. The roles of TZF genes in several plants have been well determined, whereas the functions of many non-TZF genes in plants remain uncharacterized. Herein, we describe biological and molecular functions of AtC3H12, an Arabidopsis non-TZF protein containing three CCCH zinc finger motifs. AtC3H12 has orthologs in several plant species but has no paralog in Arabidopsis. AtC3H12-overexpressing transgenic plants (OXs) germinated slower than wild-type (WT) plants, whereas atc3h12 mutants germinated faster than WT plants. The fresh weight (FW) and primary root lengths of AtC3H12 OX seedlings were lighter and shorter than those of WT seedlings, respectively. In contrast, FW and primary root lengths of atc3h12 seedlings were heavier and longer than those of WT seedlings, respectively. AtC3H12 was localized in the nucleus and displayed transactivation activity in both yeast and Arabidopsis. We found that the 97–197 aa region of AtC3H12 is an important part for its transactivation activity. Detection of expression levels and analysis of Arabidopsis transgenic plants harboring a PAtC3H12::GUS construct showed that AtC3H12 expression increases as the Arabidopsis seedlings develop. Taken together, our results demonstrate that AtC3H12 negatively affects seed germination and seedling development as a nuclear transcriptional activator in Arabidopsis. To our knowledge, this is the first report to show that non-TZF proteins negatively affect plant development as nuclear transcriptional activators.

Hypothetical protein FoDbp40 influences the growth and virulence of Fusarium oxysporum by regulating the expression of isocitrate lyase

“…In this study, we observed the regulatory effect of FoDbp40 on ICL expression (Figure 4) and demonstrated that this regulatory effect is achieved at the transcriptional level by acting on the promoter region of ICL (Figure 5). Additionally, we observed the FoDbp40 protein to localize in the nucleus (Figure 6) in line with the bioinformatic analysis (Supplementary Figure S5), which is similar to other known CCCH zinc finger protein transcription factors, including C3H12 and SAW1 (Wang et al, 2020;Seok et al, 2022). Our results indicate that FoDbp40 is a novel transcriptional regulator that can affect the expression and activity of ICL.…”