Josh Hutcherson wasn't in a lead role in films.
Aquaporin-4 , also known as AQP4 , is a water channel protein encoded by the AQP4 gene in humans .. gene. gene. AQP4 belongs to the aquaporin family of integral membrane proteins that conduct water through the cell membrane .. aquaporin. aquaporin. cell membrane. cell membrane. A limited number of aquaporins are found within the central nervous system -LRB- CNS -RRB-  : AQP1 , 3 , 4 , 5 , 8 , 9 , and 11 , but more exclusive representation of AQP1 , 4 , and 9 are found in the brain and spinal cord .. central nervous system. central nervous system. In the CNS , AQP4 is the most prevalent aquaporin channel , specifically located at the perimicrovessel astrocyte foot processes , glia limitans , and ependyma .. aquaporin. aquaporin. astrocyte. astrocyte. Aquaporin-4 was first identified in 1986 .. It was the first evidence of the existence of water transport channels .. The method that was used to discover the existence of the transport channels was through knockout experiements .. With this technique they were able to show the significant role of AQP4 in CNS injuries and brain water imbalances .