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The nature of the mesoderm-inducing signal in Xenopus: a transfilter induction study

, : The nature of the mesoderm-inducing signal in Xenopus: a transfilter induction study. Development 113(2): 661-669

A transfilter apparatus is described, which is suitable for neutralization experiments on embryonic induction, and it is used to investigate the sensitivity of the Xenopus mesoderm-inducing signal to various inhibitors. The vegetal (inducing) tissue is placed on one side of a membrane sandwich and the animal (responding) tissue on the other side. The sandwich consists of a nylon gauze in between two Nucleopore filters and enables inhibitors in the solution to have effective access to the gap between the tissues. Control experiments show a high proportion of positive inductions of a ventral character. Using this apparatus, it is shown that the protein follistatin, which effectively inhibits activin A and B in vitro, has little or no effect on the natural signal. Likewise, antibodies to basic fibroblast growth factor, which inhibit in vitro, do not inhibit the natural signal. The two inhibitors together have a slight effect. It is concluded that neither activin nor bFGF are major components of the signal emitted by the vegetal cells of the Xenopus blastula and transmitted across the liquid gap, although they might have some other role to play in the process. Two agents of lower specificity do inhibit the transfilter induction: heparin and suramin. Suramin will also inhibit induction in animal-vegetal combinations with no intervening membranes while heparin does not. This suggests that the heparin inhibition can only occur when there is a liquid gap between the tissues, presumably because it can neutralize the signal in solution but cannot penetrate the explants themselves. The endogenous mesoderm-inducing factor(s) should therefore be sensitive to heparin in vitro.


PMID: 1782872

Other references

Obenson G., 1985: Geoidal heights for Africa from GEM9 potential coefficients and degree gravity anomalies. Survey Review - Directorate of Overseas Surveys 28(218): 207-213

Rachdi, R.; Hajjami, R.; Fekih, M.A.; Messaoudi, L.; Ayari, M.; Brahim, M.; Ben Farhat, M., 1992: Characteristics of pregnancy and delivery in women with heart diseases. The authors report 78 cases of pregnancy in women with heart disease during a 4 year period (1985-1988). Heart disease involved a rheumatic valve lesion in 90 per cent of cases. Heart disease was properly monitored in these patients (74.5 per cent...

Silva, L.A.; Colocho, E.A.; Flores, J.A.; Cabezas, M.T.; Bressani, R., 1978: Early weaning in dual-purpose cattle. The following 2 systems were compared in 2 experiments over a 3-yr period with cows aged 4-6 yr, having 25% Criollo, 25% Brahman and 50% Holstein-Friesian or Brown Swiss blood: (i) weaning at 8 months, cows milked once daily (4 a.m.) without their...

Anonymous, 1974: Abstract of the symposium on immunology of psoriasis. Zhonghua Yi Xue Za Zhi 4: 249-250

Diaz-Gonzalez, V.M.; Altemose, G.T.; Ogorek, C.; Palazzo, I.; Piña, I.L., 1997: Cytomegalovirus infection presenting as an apple-core lesion of the colon. Cytomegalovirus infection is highly prevalent among heart transplant recipients. Symptomatic cytomegalovirus infection can occur in all parts of the gastrointestinal tract. Colonic lesions are usually manifest as hemorrhagic colitis. This is a cas...

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Yang, J.; Koreeda, M., 1997: Stereocontrolled synthesis of 9,10-trans-dihydrodiol and syn- and anti-diol epoxide metabolites of benzo pyrene. Abstracts of Papers American Chemical Society 214(1-2): ORGN 203

Zhurov, I.E., 1996: Features of therapeutic tactics in association of biliary calculi and thyroid diseases. Klinichna Khirurhiia: 5-7

Desai, S.A., 1998: A note on the Bud Necrosis Disease incidence in rainfed groundnut. Field experiments on thrips vectored peanut bud necrosis virus (PBNV), causal agent of Bud Necrosis Disease (BND), in rainfed groundnut in relation to crop growth stage were conducted during the rainy seasons of 1989, 1990 and 1991 in the Northern...

Anonymous, 1995: Genes in black and white. New Scientist 147(1985): 34-37