Retrospect and prospect of research on C4 photosynthesis in diatoms

Diatoms（Bacillariophyta） is one of the main groups of marine phytoplankton and plays an important role in global carbon cycle. The emergence of C4 photosynthesis is a major stride in plant evolution, and also affects the global carbon cycle. However, the understanding of C4 photosynthesis of diatoms is still limited. Since the 1970 s, scientists have argued whether C4 is involved in diatoms. In this paper, the discovery history of diatom C4 photosynthesis, the diatom carbon dioxide concentration mechanism（CCM） and the comparison of C4 photosynthesis between diatom and higher plants were reviewed. New methodology in the study of diatom’s C4 photosynthesis is prospected to know better about the role of diatoms in global carbon cycle