# Cloning and function analysis of ZmICE1a, a contributor to the melioration of maize kernel traits

## TL;DR

This study identifies and analyzes the ZmICE1a gene, which improves maize kernel traits and plant growth, offering potential for breeding higher-yield maize varieties.

## Contribution

The novel contribution is cloning and functionally characterizing ZmICE1a, a gene linked to improved maize kernel traits and plant growth.

## Key findings

- Overexpression of ZmICE1a leads to improved kernel traits and increased plant height.
- Transcriptome analysis shows ZmICE1a affects genes involved in abscisic acid signaling and metabolism pathways.

## Abstract

Kernel traits are important factors in determining maize yield. Gene mining and clarification of relevant gene functions associated with kernel traits is beneficial for breeding high-yield maize varieties. In our previous research, a critical quantitative trait locus (QTL), qKWEI3.1, associated with kernel weight was mapped using a maize F2:3 population derived from the parental lines SCML0849 and ZNC442. In the present study, qKWEI3.1 was fine-mapped, the ZmICE1a gene was cloned, and the relevant functions of ZmICE1a were dissected. The results showed that plants overexpressing ZmICE1a exhibited a shorter reproductive period, increased plant height, greater stem diameter, higher photosynthetic efficiency, and meliorated kernel traits. Transcriptome analysis revealed that ZmICE1a overexpression mediated differentially expressed genes (DEGs) such as SNRK2–10, the E3 ubiquitin-protein ligase AIP2, Pho1, and Pho2. Gene ontology and KEGG pathway enrichment analyses revealed that the DEGs were involved in the abscisic acid signaling pathway, starch, and sucrose metabolism. These results suggest that ZmICE1a is a critical, positive regulator promoting plant growth and meliorating kernel traits. The findings of this study have important implications for the improvement of grain yield through the application of genetic engineering in maize breeding.