SRS346523 SAMN01057057 GSM950662 DGE of GC-1spg 10090 Mus musculus bioproject 169095 source_name male germ cells cell line GC-1spg developmental stage stage between type B spermatogonia and primary spermatocytes SRS346524 SAMN01057058 GSM950663 DGE of GC-2spd 10090 Mus musculus bioproject 169095 source_name male germ cells cell line GC-2spd developmental stage premeiotic stage