Table 1. Factors required in transcriptional regulation of spermatogenesis.

Cell Types	Stage	Gene product(s)	Function(s)	Reference(s)
Somatic Cells	Hub cells	Gbb/Dpp	Ligand of BMP signaling pathway	Refs. 12–13
		Upd	Ligand of JAK-STAT signaling pathway	Refs. 8–10
		Magu	Regulates BMP signaling and GSC maintenance	ref. 14
	Cyst Stem Cells	Rac and Rho	Small GTPases, downstream of Egf pathway. Rac promotes Egf signaling while Rho inhibits Egf signaling. Egf pathway inhibits GSC self-renewal and promotes GSC to GB transition.	Refs. 38, 41
		pSTAT	Downstream transcription factor of JAK-STAT pathway, sufficient for GSC self-renewal	ref. 10
		Chinmo	Transcription factor, a target gene of JAK-STAT signaling, sufficient for GSC self-renewal	ref. 20
		Zfh1	Transcription factor, a target gene of JAK-STAT signaling, sufficient for GSC self-renewal	ref. 10
		Socs36E	An inhibitor and also a target gene of JAK-STAT signaling, maintains a balanced ratio of CySCs and GSCs in the niche	ref. 21
	Cyst Cells	Rac and Rho	Small GTPases, downstream of Egf pathway. Egf pathway inhibits spermatogonial division and promotes spermatogonia-to-spermatocyte transition.	Refs. 38, 41
Germ Cells	GSCs	Nucleoporin98–86	Nuclear envelope components, regulate proper GSC-to-GB transition, act upstream of BMP, JAK-STAT and Egfr pathways	ref. 40
		pMAD	Downstream transcription factor of BMP pathway, important for GSC self-renewal	Refs. 12–14
		pSTAT	Downstream transcription factor of JAK-STAT pathway, required for GSC-Hub cell adhesion	ref. 11
		Scny	A deubiquitinating enzyme targeting mono-ubiquitinated H2B, represses differentiation gene expression in GSCs	ref. 23
		NCLB	A chromatin factor that has male-specific roles for GSC maintenance through regulating JAK-STAT pathway	ref. 26
		NURF	A chromatin remodeler that positively regulates JAK-STAT signaling	ref. 22
		PHF7	An epigenetic reader that recognizes H3K4me2 and regulates GSC self-renewal	ref. 48
		miR-7	A microRNA that binds to bam mRNA 3′UTR and downregulates bam expression	ref. 34
		Msi	A RNA binding protein required for GSC maintenance	ref. 27
		HOW	A RNA binding protein required for GSC maintenance	ref. 28
		Imp	A RNA binding protein that stabilizes upd mRNA and maintains GSC	ref. 29
	Spermatogonia	Bam	A differentiation factor required for spermatogonial differentiation	Refs. 30–32
		Mael	A RNA binding protein that represses miR-7 and upregulates bam expression	ref. 34
		PHF7	An epigenetic reader that recognizes H3K4me2 and regulates spermatogonia differentiation	ref. 48
		HOW	A RNA binding protein required for spermatogonial proliferation	ref. 28
		Nucleoporin98–86	A nuclear envelope component, regulates proper spermatogonia-to-spermatocyte transition and act upstream of BMP, JAK-STAT and Egfr pathways	ref. 40
	Spermatocyte	tMAC (Aly,Achi/VisComr, Topi, Tomb,Mip40)	Regulate tTAF proper nuclear localization and binding to target genes, transcription of meiotic cell cycle and spermatid differentiation genes	Refs. 61–66, 71–73
		tTAFs) (Can, Sa, Mia, Nht, Rye)	Transcriptional activation of spermatid differentiation genes, antagonizes PcG-mediated gene silencing, accumulation of Boule protein	Refs. 69–70
		WUC	Maturation of spermatocyte and meiotic divisions	Refs. 64, 82
		THO-complex	Maturation of spermatocyte and meiotic divisions	ref. 83
		NURF	Maturation of spermatocyte and meiotic divisions	ref. 81
	Spermatid	Unknown	Post-meiotic transcription of cup and comet genes, required for individualization of sperm	Refs. 84, 90–93