ARF6s Identification and Function Analysis Provide Insights Into Flower Development of Punica granatum L.

Abstract

Based on the genome and small-RNA sequencing of pomegranate, miRNA167 and three target genes PgARF6 were identified in “Taishanhong” genome. Three PgARF6 genes and their corresponding protein sequences, expression patterns in pomegranate flower development and under exogenous hormones treatments were systematically analyzed in this paper. We found that PgARF6s are nuclear proteins with conserved structures. However, PgARF6s had different protein structures and expression profiles in pomegranate flower development. At the critical stages of pomegranate ovule sterility (8.1–14.0 mm), the expression levels of PgARF6s in bisexual flowers were lower than those in functional male flowers. Interestingly, PgARF6c expression level was significantly higher than PgARF6a and PgARF6b. Under the treatment of exogenous IBA and 6-BA, PgARF6s were down-regulated, and the expression of PgARF6c was significantly inhibited. PgmiR167a and PgmiR167d had the binding site on PgARF6 genes sequences, and PgARF6a has the directly targeted regulatory relationship with PgmiR167a in pomegranate. At the critical stage of ovule development (8.1–12.0 mm), exogenous IBA and 6-BA promoted the content of GA and ZR accumulation, inhibited BR accumulation. There was a strong correlation between the expression of PgARF6a and PgARF6b. Under exogenous hormone treatment, the content of ZR, BR, GA, and ABA were negatively correlated with the expressions of PgARF6 genes. However, JA was positively correlated with PgARF6a and PgARF6c under IBA treatment. Thus, our results provide new evidence for PgARF6 genes involving in ovule sterility in pomegranate flowers.

Exploring MicroRNAs Associated with Pomegranate Pistil Development: An Identification and Analysis Study

“…Both novel 251 and novel 171 targeted gene26063, while miR172 and novel 77 were found to target gene24967. PgmiRNA167 identified three target genes (PgARF6a, PgARF6b, and PgARF6c), and PgARF6a had a directly targeted regulatory relationship with PgmiR167a in pomegranate [29]. According to previous research results, the relationship between pomegranate miRNAs and the target genes will be confirmed in further research.…”

“…Our study found that miR167a and miR167d were expressed in the initial stage of ovule development in bisexual flowers and functional male flowers, while the expression of miR167c in the mature stage of the pistils of bisexual flowers was significantly higher than in other developmental stages and in functional male flowers. miRNA target gene prediction showed that PgmiR167a and PgmiR167d have binding sites on the PgARF6s gene sequence [29]. The results showed that PgmiR167s regulated PgARF6s expression to participate in ovule abortion in pomegranate.…”

BELL1 interacts with CRABS CLAW and INNER NO OUTER to regulate ovule and seed development in pomegranate

“…To obtain the ovule-related genes expression trends, the transcription levels of genes were obtained from pomegranate bisexual and functional male flowers transcriptome data (PRJNA754480) with vertical diameters of 5.0–10.0 mm (the first stage), 10.1–13.0 mm (the second stage), and 13.1–18.0 mm (the third stage; Zhao et al, 2022 ). RNA-seq and bioinformatics analyses were conducted by Novogene Company (Beijing, China).…”