zfh1 is expressed in neuroblasts along the ventral midline at embryonic stage 11 and then symmetrically along the midline at stages 13 and 15. It is then expressed in CNS neurons at stage 15.

Expression assayed at stages 9, 11, 13, and 17. Expression may be continuous between assayed stages in some tissues.

The zfh1 transcript distribution pattern corresponds closely to that of zfh1 protein.

zfh1 and ct proteins are differentially expressed between IFM and DFM myoblasts in wing discs. ct is expressed in myoblasts that will give rise to direct flight muscle (DFM).

zfh1 is expressed in muscle precursor cells in the wing disc. In early stages, expression is uniform but in later stages levels are reduced in cells with high ct expression that will give rise to the direct flight muscles. The cells in which zfh1 expression remains high give rise to the indirect flight muscles. zfh1 expression is observed in sparse nuclei embedded in the lamina in adult IFM. These are persistant muscle progenitor cells that remain undifferentiated in the adult. zfh1 is also expressed in another cell population in muscle that were identified as plasmatocytes.

At the embryo-larval transition, zfh1 is detected in somatic cells dispersed throughout the testes, coexpressed with tj in most but not all gonadal sheath proper primordium cells (somatic gonadal precursor cells). At the time of hub coalescence (24h AEL), somatic nuclei adjacent to the hub are enriched for zfh1 expression, in a manner characteristic of cyst progenitor cells in the adult. In early first larval instar testes (28 h AEL), high-level zfh1 expression is restricted to somatic cells adjacent to the hub, and this expression pattern persists into later stages of development.

zfh1 is expressed in all AMPs (adult muscle precursor cells.

zfh1 is expressed in all peripheral glial cells at embryonic stages 14 and 16 and in ePG12 but is excluded from other neurons and accessory cells.

zfh1 protein levels are high in cyst progenitor cells and then drop in cyst cell daughters.

Markers that uniquely identify the cells of the NB3-7 lineage were used to examine the serotonin expressing cell lineages.

zfh1 protein is initially expressed in a subset of heart precursor cells. Later expression is observed in all cells that form the dorsal vessel, cardial cells as well as pericardial cells.

zfh1 protein is abundant in staged extracts from embryos between 3 and 18 hours. zfh1 protein is first detected in the presumptive procephalic mesoderm and then in the ventral mesoderm and pole cells. In late stage 8, strong staining is seen in a ~30 cell-wide band of ventral mesoderm. In stage 11, zfh1 protein is detected mainly in ectodermally-derived CNS structures and is thought to be present in most identifiable motor neurons including the aCC, RP, VUM, ventral intersegmental, and lateral ipsisegmental neurons. In stage 13, zfh1 protein is abundant in the CNS as well as in some mesodermally derived structures, including the dorsal vessel, gonadal support cells, and laterally located adult muscle precursor cells of the thoracic and abdominal segments. At stage 15, two rows of dorsal vessel cardioblasts are strongly stained as dorsal closure is completed. The CNS has condensed and shows staining of segmentally repeated subsets of neurons. Weak staining persists in the somatic and visceral musculature.