TY - JOUR
T1 - Microsomal triglyceride transfer protein expression during mouse development
AU - Shelton, John M.
AU - Lee, Mi Hye
AU - Richardson, James A.
AU - Patel, Shailendra B.
N1 - Copyright:
Copyright 2007 Elsevier B.V., All rights reserved.
PY - 2000/4
Y1 - 2000/4
N2 - Feto-maternal transfer of lipophilic nutrients is an important factor in the normal development of the fetus and may be mediated by lipoproteins as carriers of these nutrients. Two proteins that may be important in this process are apolipoprotein B (apoB, the major structural protein of secreted lipoproteins) and microsomal triglyceride transfer protein (MTP) whose normal activity is required for the secretion of apoB-containing lipoproteins. Although no abnormalities of conception and embryonic lethality are known in humans who inherit genetic deficiencies of either of these proteins, homozygous mice bearing knockouts of either apoB or MTP show early embryonic lethality. To characterize the ontogeny of MTP expression during embryonic mouse development, we have used in situ hybridization to characterize the pattern of expression. By using microwave heating of tissue sections to optimize hybridization, we show that there is robust MTP expression in the yolk sac tissues followed by expression in the primordial liver cell nests as early as day 9 post-coitum (E9.5). Intestinal expression is detected around E12.5 and attains full adult expression patterns by E14.5. No expression in any other tissues was observed, including developing heart, kidney, placenta, and maternal decidua. Thus the pattern of MTP expression is compatible with a role in the transfer of lipophilic nutrients from the yolk sac, prior to hepatic development and to the liver, once the circulatory system has been established.
AB - Feto-maternal transfer of lipophilic nutrients is an important factor in the normal development of the fetus and may be mediated by lipoproteins as carriers of these nutrients. Two proteins that may be important in this process are apolipoprotein B (apoB, the major structural protein of secreted lipoproteins) and microsomal triglyceride transfer protein (MTP) whose normal activity is required for the secretion of apoB-containing lipoproteins. Although no abnormalities of conception and embryonic lethality are known in humans who inherit genetic deficiencies of either of these proteins, homozygous mice bearing knockouts of either apoB or MTP show early embryonic lethality. To characterize the ontogeny of MTP expression during embryonic mouse development, we have used in situ hybridization to characterize the pattern of expression. By using microwave heating of tissue sections to optimize hybridization, we show that there is robust MTP expression in the yolk sac tissues followed by expression in the primordial liver cell nests as early as day 9 post-coitum (E9.5). Intestinal expression is detected around E12.5 and attains full adult expression patterns by E14.5. No expression in any other tissues was observed, including developing heart, kidney, placenta, and maternal decidua. Thus the pattern of MTP expression is compatible with a role in the transfer of lipophilic nutrients from the yolk sac, prior to hepatic development and to the liver, once the circulatory system has been established.
KW - Embryonic development
KW - Feto-maternal unit
KW - In situ hybridization
KW - Microwave RNA retrieval
KW - Riboprobes
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M3 - Article
C2 - 10744773
AN - SCOPUS:0033993657
SN - 0022-2275
VL - 41
SP - 532
EP - 537
JO - Journal of lipid research
JF - Journal of lipid research
IS - 4
ER -