Review:  C4-like photosynthesis has important functions in C3 plant vasculature (JXB)

In contrast to the much-studied photosynthetic processes in C4 plant vasculature, the processes in the cells surrounding C3 veins remain much less understood.  Here, there appears to be a partial and more spatially-separated C4 pathway, which has been observed in several species including rice, Arabidopsis, Scots pine and celery.  In this review, Gao et al examine the evidence for this C4-like pathway, before discussing other metabolic processes that may occur in these specialised bundle sheath cells (BSCs).  They outline the evidence that C3 BSCs are involved in recapturing carbon lost during respiration, and assess the literature that supports a role for BSCs in transporting nitrogen.  A role for these cells in the sensing and signalling of reactive oxygen species is examined, before the authors conclude with assessing the influence of C3 BSCs on the development of mesophyll cells.  (Summary by Mike Page) JXB 10.1093/jxb/ery155