TY - JOUR
T1 - Is There aBrachyury the Second?Analysis of a Transgenic Mutation Involved in Notochord Maintenance in Mice
AU - Rennebeck, Gabriela M.
AU - Lader, Eric
AU - Chen, Qi
AU - Bohm, Rudy A.
AU - Cai, Zeling S.
AU - Faust, Cynthia
AU - Magnuson, Terry
AU - Pease, Larry R.
AU - Artzt, Karen
N1 - Funding Information:
This work is dedicated to the memory of L. C. Dunn, 1893±1974, belatedly on the centennial of his birth. This work was supported by NICHD Grants HD10668 and HD30658 (K.A.).
PY - 1995/11
Y1 - 1995/11
N2 - A new phenotype mapping to thet-complex, which is designatedBrachyury the Second(T2), is characterized by a slightly shortened tail in heterozygotes and homozygous failure to form an organized notochord with subsequent abnormal development of posterior somites and neural tube. The phenotype ofT2superficially resembles that ofBrachyury;however, there are several important differences.Brachyuryhomozygotes fail to make posterior somites, notochord, floor plate, and a placental connection, resulting in death by 10.5 days of development. In contrast, T2homozygotes make posterior somites, scattered notochord cells, and floorplate and achieve an allantoic connection. However, despite making a maternal connection, T2homozygotes cease development at E11.5 and die soon after. We have cloned and analyzed the transgene insertion site, which maps within 100 kb of theBrachyurygene, but does not seem to physically interrupt nor affect transcription from that locus. The existence of a second gene mapping nearBrachyuryand affecting the same developmental processes was alluded to over 50 years ago and has been debated ever since. An embryological description ofT2is presented, as is a discussion of the implications of a single, largerBrachyurylocus versus two closely linked genes coordinately regulating axial development.
AB - A new phenotype mapping to thet-complex, which is designatedBrachyury the Second(T2), is characterized by a slightly shortened tail in heterozygotes and homozygous failure to form an organized notochord with subsequent abnormal development of posterior somites and neural tube. The phenotype ofT2superficially resembles that ofBrachyury;however, there are several important differences.Brachyuryhomozygotes fail to make posterior somites, notochord, floor plate, and a placental connection, resulting in death by 10.5 days of development. In contrast, T2homozygotes make posterior somites, scattered notochord cells, and floorplate and achieve an allantoic connection. However, despite making a maternal connection, T2homozygotes cease development at E11.5 and die soon after. We have cloned and analyzed the transgene insertion site, which maps within 100 kb of theBrachyurygene, but does not seem to physically interrupt nor affect transcription from that locus. The existence of a second gene mapping nearBrachyuryand affecting the same developmental processes was alluded to over 50 years ago and has been debated ever since. An embryological description ofT2is presented, as is a discussion of the implications of a single, largerBrachyurylocus versus two closely linked genes coordinately regulating axial development.
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U2 - 10.1006/dbio.1995.0016
DO - 10.1006/dbio.1995.0016
M3 - Article
C2 - 7589801
AN - SCOPUS:0028973417
SN - 0012-1606
VL - 172
SP - 206
EP - 217
JO - Developmental Biology
JF - Developmental Biology
IS - 1
ER -