A homeodomain feedback circuit underlies step-function interpretation of a Shh morphogen gradient during ventral neural patterning.
Lek M, Dias JM, Marklund U, Uhde CW, Kurdija S, Lei Q, Sussel L, Rubenstein JL, Matise MP, Arnold HH, Jessell TM, Ericson J. A homeodomain feedback circuit underlies step-function interpretation of a Shh morphogen gradient during ventral neural patterning. Development. 2010 Dec; 137(23):4051-60.