MAP3K1 and bacterial infectious disease: In addition, two of the four genes that were down-regulated in all conditions are involved in the innate immune response: Ser8, which encodes a serine protease induced by bacterial infection; and CG4950, to which encodes a transcriptional target of the Mekk1 pathway following bacterial infection (De Gregorio et al. 2001; Chakrabarti et al. 2014).