TY - JOUR
T1 - Differential regulation of the zinc finger genes Krox-20 and Krox-24 (Egr-1) suggests antagonistic roles in Schwann cells
AU - Topilko, Piotr
AU - Levi, Giovanni
AU - Merlo, Giorgio
AU - Mantero, Stefano
AU - Desmarquet, Carole
AU - Mancardi, Gianluigi
AU - Charnay, Patrick
PY - 1997/12/1
Y1 - 1997/12/1
N2 - Krox-20 and Krox-24 (Egr-1) encode closely related zinc finger transcription factors, which interact with the same DNA target sequences. Krox-20 is required for myelination in the peripheral nervous system. Using lacZ knock-in mutant mouse lines as well as immunohistochemical analyses, we have studied the expression of Krox-20 and Krox-24 in the Schwann cell lineage during normal development and following nerve lesion in the mouse and in human neuropathies. During embryogenesis, the two genes are expressed in a successive and mutually exclusive manner, Krox-24 being restricted to Schwann cell precursors and Krox-20 to mature Schwann cells. At birth, Krox-24 is reactivated and the two genes are coexpressed. In the adult, Krox-20 is expressed in myelinating cells, while Krox-24 is restricted to nonmyelinating cells. Following nerve lesion, Krox-24 is strongly induced in Schwann cells, reinforcing the link between its expression and the nonmyelinating and/or proliferative state, whereas Krox-20 is downregulated. These data are consistent with Krox-20 and Krox-24 playing antagonistic roles during the development of the Schwann cell lineage. In particular, their balance of expression might participate in the choice between myelinating and nonmyelinating pathways.
AB - Krox-20 and Krox-24 (Egr-1) encode closely related zinc finger transcription factors, which interact with the same DNA target sequences. Krox-20 is required for myelination in the peripheral nervous system. Using lacZ knock-in mutant mouse lines as well as immunohistochemical analyses, we have studied the expression of Krox-20 and Krox-24 in the Schwann cell lineage during normal development and following nerve lesion in the mouse and in human neuropathies. During embryogenesis, the two genes are expressed in a successive and mutually exclusive manner, Krox-24 being restricted to Schwann cell precursors and Krox-20 to mature Schwann cells. At birth, Krox-24 is reactivated and the two genes are coexpressed. In the adult, Krox-20 is expressed in myelinating cells, while Krox-24 is restricted to nonmyelinating cells. Following nerve lesion, Krox-24 is strongly induced in Schwann cells, reinforcing the link between its expression and the nonmyelinating and/or proliferative state, whereas Krox-20 is downregulated. These data are consistent with Krox-20 and Krox-24 playing antagonistic roles during the development of the Schwann cell lineage. In particular, their balance of expression might participate in the choice between myelinating and nonmyelinating pathways.
KW - Demyelinating neuropathies
KW - Nerve regeneration
KW - Peripheral nerve
KW - Schwann cell development
UR - http://www.scopus.com/inward/record.url?scp=0030696010&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0030696010&partnerID=8YFLogxK
U2 - 10.1002/(SICI)1097-4547(19971201)50:5<702::AID-JNR7>3.0.CO;2-L
DO - 10.1002/(SICI)1097-4547(19971201)50:5<702::AID-JNR7>3.0.CO;2-L
M3 - Article
C2 - 9418958
AN - SCOPUS:0030696010
VL - 50
SP - 702
EP - 712
JO - Journal of Neuroscience Research
JF - Journal of Neuroscience Research
SN - 0360-4012
IS - 5
ER -