Successful male gametogenesis and tolerance to interploidy crosses both require WRKY transcription factors. These processes are outlined in the article gametogenesis. Importins are vital regulatory proteins during the processes of gametogenesis and embryogenesis. Gametes are produced within the gonads through a process known as gametogenesis. Gametogonia are usually seen as the initial stage of gametogenesis. Populations have been found to synchronize their gametogenesis and spawning activities. These gonadotropic hormones lead to sexual maturation and gametogenesis. An oocyte is produced in the ovary during female gametogenesis. The Y chromosome is passed exclusively through sperm, which undergo multiple cell divisions during gametogenesis. Such mutations occur throughout the mouse chromosomes as well as during different stages of gametogenesis. If the adult mussels are stressed during the beginning of gametogenesis, the process is terminated. Sexual reproduction in "Trichonympha" occurs in three distinct phases&colon; gametogenesis, fertilization and meiosis. This is due to a mis-segregation (nondisjunction) during gametogenesis. DNMT3L is expressed during gametogenesis when genomic imprinting takes place. Fusomes were previously thought to be specific to insect gametogenesis.