The serpent gene is necessary for progression through the early stages of fat-body development.

The serpent (srp) gene, also known as ABF, codes for a GATA-like transcription factor and is involved in the transcription activation of Adh in the larval fat body or adipose tissue. Here, we describe the tissue-specific distribution of SRP protein in various stages of embryonic development and describe srp's role in early fat-cell development. SRP protein was detected in the progenitor fat-body cells and is present in the developing fat-body cells and in the mature embryonic fat body. An analysis of srp embryos revealed a gradual loss of precursor fat cells that is likely due to apoptosis. Within the fat-cell lineage, srp is necessary for progression through early stages of fat-cell development and may be involved in the transactivation of genes necessary for fat-cell differentiation.