Overexpression of AtHsfB4 induces specific effects on root development of Arabidopsis

► Functions of plant class B-heat shock factors (HSF) are poorly understood. ► Arabidopsis HsfB4 shows a special expression pattern in root tissue. ► Transgenic overexpression results in abnormal growth in root meristematic region. ► Extra layers of endodermis and lateral root cap cells are formed. ► HsfB4 controls early stages of root development.