Selective expression of a novel high-affinity transport system for acidic and neutral amino acids in the tapetum cells of Arabidopsis flowers.

摘要: Summary Within the flower, microsporogenesis represents a major sink for nitrogen, but knowledge on how imported nitrogen is transferred from anther cell layers to developing pollen lacking. Here, we provide information characterization of transporter (AtLHT2) that might play an important role in partitioning amino acids microspore development. Biochemical analysis yeast showed AtLHT2 transports proline and aspartate with high affinity. However, other neutral acidic act as strong competitors uptake indicating generally uncharged negatively charged acids. Comparison apparent Km values previously characterized acid transporters clearly demonstrated novel high-affinity system Northern blot expression flower buds. Cellular could be resolved by using RNA situ hybridization RT-PCR methods, which localized specifically tapetum tissue anthers. Developing grains are symplasmically isolated sporophytic rely nutrients compounds secreted cells. Thus, functional AtLHT2, together our localization studies, strongly suggest Arabidopsis flowers, has critical function import into cells synthesis structure transfer organic locule