A Novel Tandem Zinc Finger Protein in Gossypium hirsutum, GhTZF2, Interacts with GhMORF8 to Regulate Cotton Fiber Cell Development

Abstract

Arginine-rich Tandem Zinc Finger (RR-TZF) proteins make up a plant-specific superfamily that participates in plant development, while their roles in cotton fiber development remain to be explored. In this study, we identified an RR-TZF protein-coding gene, GhTZF2, containing two CCCH domains (C-X7-C-X5-C-X3-H-X16-C-X5-C-X4-C-X3-H) and one RR domain at the N-terminus of the two CCCH domains, by comparing the differences of chromatin H3K4me3 modifications between wild-type upland cotton (WT) and the fuzzless-lintless mutant (fl) ovules. GhTZF2 was highly expressed in ovule cells near anthesis, and multiple experiments revealed that GhTZF2 could interact directly with GhMORF8. Homozygotic GhTZF2-knockout cotton lines produced significantly shorter fibers with thinner cell walls. Additionally, comparative transcriptome analysis confirmed that many differentially expressed transcripts contain adenine- and uridine-rich (AU-rich) elements (AREs) in their 3’ untranslated regions (UTR). Together, this study indicated that GhTZF2 may regulate cotton fiber cell development through interacting with GhMORF8, or may be involved in mRNA turnover.

Stress Granule Protein TZF1 Enhances Salt Stress Tolerance by TargetingACA11mRNA for Degradation in Arabidopsis

“…6C). Among which, the autoinhibited Ca 2+ -ATPase genes ACA11 and ACA9 encoding calcium pumps (Li et al, 2023), KAT3 encoding a subunit of potassium channel (Sun et al, 2015), ARP1 encoding an ABA-regulated RNA-binding protein 1 (Jung et al, 2013), and Hsp90.5 encoding a heat shock protein (Song et al, 2009) are all implicated in playing a negative role in salt stress tolerance response. RIP-qPCR results showed that TZF1, but not the TZF H186Y , could bind the F1 region of ACA11 mRNA (Figs.…”

“…One potential candidate is ACA11 (Fig. 6C), a tonoplast-localized Ca 2+ pump (like ACA4 ) (Li et al, 2023). Salt stress is known to result in Ca 2+ accumulation in the cytoplasm where it functions as an important secondary messenger to trigger a complex signal transduction pathway to enhance salt stress tolerance (Zhao et al, 2021).…”

Genetic and Molecular Regulation of Cotton Fiber Initiation and Elongation

“…This suggests the operation of similar mechanisms for fiber initiation in these two fiberless lines. The study sheds light on the regulatory networks mediated by GhMML3 and GhVIN1 in controlling fiber initiation in cotton [33].…”

“…Comparative transcriptome analysis between the natural fiberless mutant XZ142FLM and the transgenic fiberless line GhVIN1i, obtained by RNAi silencing of GhVIN1, identified common differentially expressed genes (DEGs) in ovules during fiber initiation. The respective DEGs were enriched in several identical pathways related to fiber initiation, revealing shared molecular regulatory networks controlling fiber initiation [33]. Several genes related to fiber initiation or elongation, such as GhMML3, GhVIN1, GhMYB25, GhHD-1, and GhHOX3, exhibited similar expression patterns in mutant XZ142FLM and the RNAi mutant GhVIN1i during fiber early development.…”

“…In another notable finding, a novel tandem CCCH Zinc Finger (TZF), GhTZF2, was discovered to regulate cotton fiber development. GhTZF2 exhibited high expression in ovule cells during the very early stages of fiber development, and knockout lines of GhTZF2 produced significantly shorter fibers with thinner cell walls, underscoring its crucial role in the modulation of cotton fiber development [33]. Recently, Liu and colleagues found that Zinc Finger Protein8 (GhZFP8) encoding a C2H2 transcription factor were abundant at 3, 6 and 30 DAP during the fiber elongation.…”