Though GNC and CGA1 have partially redundant roles in controlling chloroplast development, our results indicate they have partially divergent functions, with CGA1 exhibiting a more direct influence over cytokinin and GA-related developmental processes. As predicted by co-expression analysis, we found that GNC had a more significant effect on chloroplast development, while CGA1 plays a more prominent role in maintaining the balance between cytokinin and gibberellins signaling Unlike Richter et al., we did not observe significant differences in germination or the timing of developmental events in GNC transgenic lines. Previous studies have also failed to report a significant difference in the flowering time of the gnc mutant. If GNC GDC-0941 exerts control over this process, we would expect to see reciprocal differences between the mutant and over-expression lines as seen for CGA1. We speculate that this discrepancy in flowering time reported for GNC over-expression lines may be due to minor variations in growth conditions, such as light and nitrogen levels. It is also possible that different levels of overexpression may result in variations in phenotype, with higher than our observed 4- fold increase causing a more significant effect. Just as increased concentrations of cytokinin result in a more significant influence on plant growth, differences in the level of expression of either GNC or CGA1 may exacerbate phenotypes related to cytokinin and GA signaling. Still, results suggest that GNC and CGA1 have at least partially redundant roles and act at an important hub where light, nitrogen, cytokinin and GA signaling all converge. Modification of both gibberellin and cytokinin signaling pathways has been used to increase agricultural productivity. Cross-talk between GA and cytokinin may involve differential regulation of transcription factors by these hormone signaling pathways. The control of GNC and CGA1 expression appears to represent a pivotal point in the cross-talk between cytokinin and GA for regulating chloroplast development, possibly by influencing the amount of nitrogen being assimilated. Understanding how plants regulate chloroplast development has important implications for agricultural biotechnology. Crop plants require copious amounts of XAV939 applied nitrogen fertilizer and crop yield is typically proportional to the amount of nitrogen available in the soil. Field conditions are not always optimal and crops typically experience periods of decreased light, water and nutrients. Uneven application of fertilizer and leeching of nitrogen from the soil also contributes to reduced yields. Being able to maintain chlorophyll levels even when light and nitrogen are not abundant could be beneficial to crop plants.