# Beware of Sealing Film of Petri Dishes!—Alters the Expression of a Large Number of Genes

## TL;DR

Sealing Petri dishes with plastic wrap or parafilm alters gene expression in Arabidopsis seedlings, affecting growth and oxygen-related biological processes.

## Contribution

This study reveals that sealing materials significantly alter gene expression in plants, highlighting the importance of experimental setup in biological research.

## Key findings

- Sealing with PE plastic wrap and PP parafilm caused over 1000 differentially expressed genes in Arabidopsis seedlings.
- CO2 levels dropped in sealed dishes, correlating with gene expression changes related to hypoxia response.
- Growth reduction and gene expression shifts were observed even without significant changes in oxygen levels.

## Abstract

Arabidopsis seedlings grown in Petri dishes sealed with PE plastic wrap, PP parafilm, or NF surgical tape showed differences in growth, with PE plastic wrap resulting in a smaller size and fresh weight, followed by PP parafilm, compared to unsealed or NF surgical tape-sealed dishes. To investigate the basis of these phenotypic changes, transcriptome sequencing was performed. The results indicated that seedlings in dishes sealed with PE plastic wrap and PP parafilm exhibited over 1000 differentially expressed genes (DEGs) at 7 days. By 14 days, the number of DEGs had increased to over 2000 for each sealed condition. GO analysis showed that DEGs were commonly enriched in biological processes associated with the response to hypoxia under PE plastic wrap and PP parafilm sealing at both 7 and 14 days, as well as under NF surgical tape at 14 days. While O2 levels showed no significant differences between sealed and unsealed conditions, CO2 concentrations were notably lower in plates sealed with PE plastic wrap and PP parafilm. Furthermore, specific genes related to reduced size and delayed growth under sealed conditions were identified. In summary, sealing films negatively affect seedling growth, leading to significant shifts in gene expression profiles.