Phenotype Image Detail

Image

Caption

Influence of Lfng presomitic mesoderm (PSM) domains on segmentation and extension of the tail. (A-F) Transgenic Lfng stripe expression improves somite compartmentalization only in the tail. (A-C) Cranial-caudal somite compartmentalisation in Lfng^tm1Rjo/Lfng^tm1Rjo (Lfng-/-) embryos (visualised by in situ hybridization with Uncx4.1) is irregular in the cranial body half but regular in the sacral (red box) and first tail somites. Lfng^tm1Rjo/Lfng^tm1Rjo E11.5 tails are shorter than wild-type-like Lfng⁺/Lfng^tm1Rjo (Lfng+/-) tails (compare C and D). The lack of Uncx4.1 stripes close to the PSM suggests that segmentation has ceased in the mutant (red bar in C). (E, F) Transgenic cLfng expression in 5kL-1/0 (Tg(Lfng-LFNG)1Dihz/0 Lfng^tm1Rjo/Lfng^tm1Rjo) almost fully rescues compartmentalisation in trunk and tail (arrows in F indicate occasional irregular stripes). (G-I) Transgenic cLfng expression in BBL lines [G, Tg(Lfng*-LFNG)1Dihz/Tg(Lfng*-LFNG)1Dihz Lfng^tm1Rjo/Lfng^tm1Rjo (BBL-1/BBL-1); H, Tg(Lfng*-LFNG)1Dihz/0 Lfng^tm1Rjo/Lfng^tm1Rjo (BBL-1/0); I, Tg(Lfng*-LFNG)2Dihz/0 Lfng^tm1Rjo/Lfng^tm1Rjo (BBL-2/0)] rescues cranial-caudal compartmentalisation mainly in the tail (arrows in I indicate irregular stripes). (J-O) Lfng is important for clear separation of sclerotomes (ventral compartments of somites) except for those in the sacrum, and influences dorsal-ventral patterning of the paraxial mesoderm of the tail. Sclerotomes (stained with Pax-1) are regular and segmented in wild-type mice (J, K) but enlarged and undefined in Lfng^tm1Rjo/Lfng^tm1Rjo embryos except in the sacral area (L, M). 10 mm transverse sections of embryos in K and M at tail region indicated by a dash (N, O; same magnification) counterstained with nuclear fast red (Vector Labs) show an increase in sclerotome size in the mutant (Pax1-positive area encircled with a dashed line on right side of sections). (P-U) Expression of PSM markers Fgf8 (P-R; red arrows point at PSM expression in the tail; expression in Q is weak and restricted, and undetectable in slightly older embryos, not shown) and Tbx6 (S-U) is indistinguishable between heterozygous and homozygous Lfng^tm1Rjo embryos. The PSM is boxed in blue. Forelimb buds (fl) align to somites, 8-14, hindlimb buds (hl) to somites, 25-30; nt, neural tube.

Copyright

This image is from Stauber M, PLoS One 2009;4(11):e7996, and is displayed under the terms of the Creative Commons Attribution 4.0 International License. J:155378

Associated Alleles

Symbol	Name
Lfng^tm1Rjo	LFNG O-fucosylpeptide 3-beta-N-acetylglucosaminyltransferase; targeted mutation 1, Randy L Johnson
Tg(Lfng-LFNG)1Dihz	transgene insertion 1, David Ish-Horowicz
Tg(Lfng*-LFNG)1Dihz	transgene insertion 1, David Ish-Horowicz
Tg(Lfng*-LFNG)2Dihz	transgene insertion 2, David Ish-Horowicz

Associated Genotypes

Allelic Composition	Genetic Background
Lfng^tm1Rjo/Lfng^tm1Rjo	involves: 129S7/SvEvBrd
Lfng^tm1Rjo/Lfng^tm1Rjo Tg(Lfng*-LFNG)1Dihz/Tg(Lfng*-LFNG)1Dihz	involves: 129S7/SvEvBrd * C57BL/6J * CBA
Lfng^tm1Rjo/Lfng^tm1Rjo Tg(Lfng*-LFNG)1Dihz/0	involves: 129S7/SvEvBrd * C57BL/6J * CBA
Lfng^tm1Rjo/Lfng^tm1Rjo Tg(Lfng*-LFNG)2Dihz/0	involves: 129S7/SvEvBrd * C57BL/6J * CBA
Lfng^tm1Rjo/Lfng^tm1Rjo Tg(Lfng-LFNG)1Dihz/0	involves: 129S7/SvEvBrd * C57BL/6J * CBA