Jingxin Chen

Proteomic Analysis of Mechanisms Responsible for the Waterless Preservation of Fenneropenaeus chinensis Based on Cold-Forced Hibernation

ABSTRACT In this study, the comparative proteomic approach was used to identify the proteins that were changed significantly during the waterless preservation of Chinese white shrimp (Fenneropenaeus chinensis). Approximately 380–430 protein spots were observed in the two-dimensional protein electrophoresis (2-DE) gels. Among them, 14 altered proteins from hemolymph were excised and subjected to matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) analysis. Eleven protein spots were successfully identified—including hemocyanin, hemolymph clottable protein, myosin light chain, and sarcoplasmic calcium-binding protein. It could be speculated that the combined action of decreased hemocyanin, increased hemolymph clottable protein, and myosin light chain forced Chinese white shrimp into a temporary state of hibernation under cold temperature and could keep the hibernated shrimps alive during the waterless preservation. Moreover, increased expression of sarcoplasmic calcium-binding protein ensured that hibernated shrimps could be aroused at warm temperature. On the basis of these findings, it is believed that a protein-protein networking mechanism of hemocyanin, hemolymph clottable protein, myosin, and sarcoplasmic calcium-binding protein could interpret the cold-forced hibernation and warm-arousal of Chinese white shrimp.

Cucumber BAX inhibitor-1, a conserved cell death suppressor and a negative programmed cell death regulator under cold stress

Programmed cell death (PCD) is a genetically controlled and conserved process in eukaryotes during development as well as in response to pathogens and other stresses. BAX inhibitor-1 (BI-1) has been implicated as an anti-PCD factor which is highly conserved in plants. Sequence of putative cucumber BI-1 protein exhibited 77.7 % identity and 91.2 % positive value with the homologue Blast BI-1 protein of Arabidopsis thaliana (AtBI-1). This highly homologous protein to the AtBI-1 protein was named CsBI-1. This protein contains an open reading frame (ORF) of 250 amino acids with a BAX inhibitor domain and five transmembrane regions conserved among members of the BI-1 family. Primers designed by the cDNA of CsBI-1gene were used for further sequencing. Cell death in cold-stored cucumber developed concomitantly with increased expression of the CsBI-1 gene and reached maximum at day 6. However, cell death accelerated significantly after 9 d when sharp decrease of the CsBI-1 expression occurred. After warming to 20 °C, expression of the CsBI-1 gene was the highest at day 3, decreased afterwards, and the lowest expression was detected at day 9 when PCD obviously appeared. The overall results indicate that CsBI-1 is cucumber homologue of Arabidopsis thaliana AtBI-1 gene. CsBI-1 is a conserved cell death suppressor induced by cold stress and a negative regulator of PCD.