Characterization and function of the urea transporter genes from Porphyra yezoensis (Rhodophyta) in molecular mechanisms underlying assimilation of nitrogen sources

在条斑紫菜中发现了两个尿素转运蛋白(PyUT1和PyUT2)，它们可能参与氮素的吸收和同化。在低氮条件下，PyUT1和PyUT2基因的表达迅速被诱导，这表明在低氮条件下，PyUT基因可能在适应低氮条件中起着重要作用。无机氮源和有机氮尿素对PyUT1和PyUT2基因的表达均有影响。将该表达载体转化酵母UT(DUR3)基因突变株，未观察到这些转化子的生长互补性。这些结果表明，PyUT基因在其他氮源的吸收和/或胞内尿素转运系统中起着重要作用。

Two urea transporters (PyUT1 and PyUT2), which may be involved in nitrogen uptake and assimilation, have been identified in the rhodophyta seaweed Porphyra yezoensis. Expression of both PyUT1 and PyUT2 genes were rapidly induced under low nitrogen concentration, suggesting a possibility that the PyUT genes play an important role in adaptation to low nitrogen conditions. The expression levels of both PyUT1 and PyUT2 genes were affected by inorganic nitrogen sources and an organic nitrogen urea. When the yeast UT (DUR3) gene-mutant strain was transformed with the plasmid vector expressing PyUT1 or PyUT2 proteins, the growth complementation of these transformants was not observed. These results suggest that the PyUT genes play important roles in uptake of other nitrogen sources and/or in intracellular urea transport system.