The present invention provides a polynucleotide comprising all or a part of the nucleotide sequence identified as SEQ ID NO:1 that regulates transcription of the human high-affinity IgE receptor (Fc.epsilon.FI) .beta.-chain gene, and a method for regulating transcription of the Fc.epsilon.FI .beta.-chain gene which comprises the step of promoting binding between a transcription regulatory complex containing MZF-1 and the transcription regulatory region of the Fc.epsilon.FI .beta.-chain gene that contains the nucleotide sequence identified as SEQ ID NO: 1. In addition, the present invention provides a screening method and a kit therefor that utilizes the method for regulating transcription of the Fc.epsilon.FI .beta.-chain gene having the step of promoting binding between a transcription regulatory complex containing MZF-1 and the transcription regulatory region of the Fc.epsilon.FI .beta.-chain gene that contains the nucleotide sequence identified as SEQ ID NO:1, thereby enabling development of a novel agent for the prevention and treatment of allergic diseases.