Proteomic, transcriptomic, biochemical and physiological investigations
shed light on responses to low temperature stress in two contrasting
soybean varieties
Abstract
Cold stress is the major abiotic factor limiting crop productivity.
However, compared to model plant Arabidopsis thaliana, crucial
genes and underlying molecular mechanisms involved in soybean cold
stress remain underexplored. Here, we investigate two national soybean
cultivars, HH43 and HX3, bred from northeast and southwest regions of
China, which exhibit significant differences in cold tolerance.
Morphological and biochemical examinations show that, compared to HH43,
HX3 exhibits delayed wilting, reduced oxidative damage, and elevated
antioxidant enzyme activities under low temperature (4°C).
Transcriptomic analyses at different time courses upon 4°C show distinct
patterns, with HH43 having a rapid gene response and HX3 exhibiting a
gradual increase. Particularly, we identify MEblue and MEgreen modules
related to cold stress and construct their GENIE3 networks. Key TFs such
as CAMTA1/A2 , WRKY33/40 , ATAF1 , ERF72, bZIP29
and their potential targets were identified, which likely contribute to
the cold tolerance differences between HH43 and HX3. Moreover, proteomic
analyses reveal a broader and more sustained protein upregulation
associated with maintaining metabolic activity and cellular homeostasis
in cold-tolerant HX3, while limited proteomic response was observed in
cold-sensitive HH43 and degradation of certain early response proteins.
These findings provide substantial resources for further functional
research and breeding cold-tolerant soybean cultivars.