# Determining the Role of OsAGP6P in Anther Development Within the Arabinogalactan Peptide Family of Rice (Oryza sativa)

## TL;DR

This paper identifies OsAGP6P as a key gene in rice pollen development, showing its role in fertility and plant traits.

## Contribution

The first detailed analysis of AG peptide genes in rice, focusing on OsAGP6P's role in pollen development.

## Key findings

- OsAGP6P is expressed in rice stamen during critical pollen development stages.
- Overexpression of OsAGP6P reduces seed-setting rate and plant height but increases tillering.
- AGP6P is linked to pollen maturation and fertility in rice.

## Abstract

Arabinogalactan proteins (AGPs) are complex proteoglycans present in plant cell walls across the kingdom. They play crucial roles in biological functions throughout the plant life cycle. In this study, we identified 43 gene members of the AG peptide (an AGP subfamily) within the rice genome, detailing their structure, protein-conserved domains, and motif compositions for the first time. We also examined the expression patterns of these genes across 18 tissues and organs, especially the different parts of the flower (anthers, pollen, pistil, sperm cells, and egg cells). Interestingly, the expression of some AG peptides is mainly present in the pollen grain. Transcription data and GUS staining confirmed that OsAGP6P—a member of the AG peptide gene family—is expressed in the stamen during pollen development stages 11–14, which are critical for maturation as microspores form after meiosis of pollen mother cells. It became noticeable from stage 11, when exine formation occurred—specifically at stage 12, when the intine began to develop. The overexpression of this gene in rice decreased the seed-setting rate (from 91.5% to 30.5%) and plant height (by 21.9%) but increased the tillering number (by 34.1%). These results indicate that AGP6P contributes to the development and fertility of pollen, making it a valuable gene target for future genetic manipulation of plant sterility through gene overexpression or editing.