Table 5.

Comparison of ‘fixing’ effects of mahogunin protein overexpression on Nodal, Lefty and Pitx2 laterality and organ situs and the degree of repair of incorrect laterality, calculated as the percentage of embryos with incorrect Nodal expression that have correct organ situs, using separate or same clutches for each analysis. R: right; Bi: bilateral; N: none. Mgrn G2A is a membrane localization mutant, and Mgrn C314D a mutant form of the protein which inhibits its function as an ubiquitin ligase of α-tubulin. Ect2-trunc, unlike mahogunin, affects left–right patterning when overexpressed at later timepoints post-fertilization as well as immediately post-fertilization. Degree of repair for Mgrn wt and Mgrn G2A indicates that defects in early laterality markers are being corrected by the point of organ placement.

proteinincorrect Nodal expressionincorrect Lefty expressionincorrect Pitx2 expressionreversed organsdegree of repair
separate clutches
control7%
(R: 1%, Bi: 2%, N: 4%)
n = 1632
3%
(R: 0%, Bi: 1%, N: 2%)
n = 597
4%
(R: 0%, Bi: 2%, N: 2%)
n = 428
1%
n = 9686
86%
Mgrn wt44%
(R: 10%, Bi: 23%, N: 11%)
n = 390
8%
(R: 0%, Bi: 0%, N: 8%)
n = 91
4%
(R: 0%, Bi: 0%, N: 4%)
n = 79
6%
n = 355
91%
Mgrn G2A26%
(R: 4%, Bi: 10%, N: 12%)
n = 200
20%
(R: 3%, Bi: 1%, N: 16%)
n = 161
23%
(R: 6%, Bi: 10%, N: 7%)
n = 160
15%
n = 199
42%
Mgrn C314D14%
(R: 1%, Bi: 8%, N: 5%)
n = 160
8%
(R: 4%, Bi: 4%, N: 0%)
n = 108
14%
(R: 0%, Bi: 7%, N: 7%)
n = 106
17%
n = 209
−21%
Ect2-trunc24%
(R: 6%, Bi: 8%, N: 10%)
n = 283
27%
(R: 10%, Bi: 2%, N: 15%)
n = 165
34%
(R: 12%, Bi: 12%, N: 10%)
n = 118
25%
n = 101
−4%
same clutches
control9%
(R: 1%, Bi: 2%, N: 5%)
n = 200
14%
(R: 1%, Bi: 0%, N: 13%)
n = 58
0%
(R: 0%, Bi: 0%, N: 0%)
n = 54
1%
n = 1139
88%
Mgrn wt37%
(R: 6%, Bi: 23%, N: 8%)
n = 161
7%
(R: 0%, Bi: 5%, N: 2%)
n = 45
9%
(R: 3%, Bi: 3%, N: 3%)
n = 44
3%
n = 204
92%
Mgrn C314D25%
(R: 6%, Bi: 9%, N: 10%)
n = 133
22%
(R: 0%, Bi: 12%, N: 10%)
n = 45
39%
(R: 5%, Bi: 5%, N: 29%)
n = 48
20%
n = 200
20%
Ect2-trunc44%
(R: 8%, Bi: 17%, N: 19%)
n = 35
50%
(R: 25%, Bi: 15%, N: 10%)
n = 25
48%
(R: 17%, Bi: 9%, N: 22%)
n = 23
28%
n = 132
36%