TUBG1 and Nematoda infectious disease: However, in spite of apparent down-regulation of TUBG1 and TUBG2 expression in mature syncytia, the nematode infection and development tests performed on tubg1-1 and tubg2-1 mutants showed that the lack of expression of any of γ-tubulin genes significantly decreased numbers of infecting juveniles and maturing nematode females whereas the development of males was uninfluenced.