C3H-type zinc finger proteins have been known to play important roles in
plant growth, development, and stress responses. The team of Ming Jiang of
Taizhou University in China aimed to study a C3H-type zinc finger gene from
broccoli (Brassica oleracea var. italica) designated as BoC3H.
The transcripts of BoC3H were found to be induced by NaCl, with the highest
expression levels observed at 18h after treatment. Four broccoli lines
overexpressing BoC3H gene were then developed. These lines exhibited higher
germination rates, dry weight and chlorophyll content in response to salt
stress compared to wild type plants.
Further analysis showed that overexpression of BoC3H significantly decreased
hydrogen peroxide levels, relative electrical conductivity (REC) and
malondialdehyde (MDA) contents, while dramatically increasing free proline
content, catalase, peroxidase and superoxide dismutase enzyme activities.
These resulted in less cell death in the leaves of transgenic plants.
These results suggest that BoC3H contributes to salt stress tolerance by
regulating hydrogen peroxide levels, REC, free proline, MDA, and antioxidant
enzyme levels in broccoli.