Figure 1. GNC inlfuences chlorophyl content but does not directly regulate sugar signalling or transport.

A) Expression levels of CGA1 and GNC in the HEXOKINASE1 mutant (gin2) using qRT-PCR from 3 week old rosette leaf tissue. B) Cotyledon expansion (where cotyledons open but appear pale and etiolated) and cotyledon greening (where expanded cotyledons also produce chlorophyll) of transgenic lines compered to wild-type on high glucose (6%) MS media. C) Images of 3 week old Wt-Ler, gnc-Ler, gin2 and gin2/gnc plants. D) Chlorophyll content measured with the standard acetone extraction and with the Minolta SPAD 502DL meter. Due to the decreased leaf and cell size of the gin2 mutant, using the acetone based extraction technique that controls for biomass requires a larger number of leaves/cells to be harvested for comparative analysis. Results taken with the SPAD meter are nondestructive and use light transmitted through a single leaf. Both techniques demonstrate that the gin2/gnc double mutant lacks chlorophyll accumulation, though the SPAD readings show less variation and are not as influenced by overall differences in plant size (All data MEAN±SD, * indicates p≤.05, t-test).