Figure - PMC

Skip to main content

An official website of the United States government

Here's how you know

Here's how you know

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you've safely connected to the .gov website. Share sensitive information only on official, secure websites.

View full-text article in PMC

. 1999 Mar 22;144(6):1337–1348. doi: 10.1083/jcb.144.6.1337

Search in PMC
Search in PubMed
View in NLM Catalog
Add to search

This article is distributed under the terms of an Attribution–Noncommercial–Share Alike–No Mirror Sites license for the first six months after the publication date (see http://www.rupress.org/terms). After six months it is available under a Creative Commons License (Attribution–Noncommercial–Share Alike 4.0 Unported license, as described at http://creativecommons.org/licenses/by-nc-sa/4.0/).

PMC Copyright notice

Cross talk between insulin and BM signaling pathways. Mammary cells cultured on either collagen I or BM were stimulated for 15 min with insulin or left unstimulated. (A) Cell lysates were immunoprecipitated with anti-insulin receptor β (Ins-Rβ) antibody and precipitated proteins were analyzed by immunoblotting for phosphotyrosine (4G10; top). Equivalent amounts of insulin receptor β were confirmed by SDS-PAGE of the same amount of whole cell lysate followed by immunoblotting with anti-insulin receptor β antibody (bottom). (B) Duplicate cell lysates were immunoprecipitated with anti–IRS-1 antibody and precipitated proteins were analyzed by immunoblotting for either phosphotyrosine using 4G10 (top) or for IRS-1 itself to confirm that equal levels of IRS-1 were present in all the samples (bottom). (C) Association of PI 3-kinase with IRS-1 was determined by immunoprecipitating lysates with anti–IRS-1 antibody, followed by immunoblotting with antibodies to either phosphotyrosine, the p85 subunit of PI 3-kinase (p85), or the precipitating antibody. (D) The signal from the experiment in C was quantitated by scanning densitometry and the level of phosphotyrosine or PI 3-kinase in each sample was normalized to the level of IRS-1. Note that threefold more PI 3-kinase associated with IRS-1 in cells cultured on BM than in cells cultured on collagen I.

Cross talk between insulin and BM signaling pathways. Mammary cells cultured on either collagen I or BM were stimulated for 15 min with insulin or left unstimulated. (A) Cell lysates were immunoprecipitated with anti-insulin receptor β (Ins-Rβ) antibody and precipitated proteins were analyzed by immunoblotting for phosphotyrosine (4G10; top). Equivalent amounts of insulin receptor β were confirmed by SDS-PAGE of the same amount of whole cell lysate followed by immunoblotting with anti-insulin receptor β antibody (bottom). (B) Duplicate cell lysates were immunoprecipitated with anti–IRS-1 antibody and precipitated proteins were analyzed by immunoblotting for either phosphotyrosine using 4G10 (top) or for IRS-1 itself to confirm that equal levels of IRS-1 were present in all the samples (bottom). (C) Association of PI 3-kinase with IRS-1 was determined by immunoprecipitating lysates with anti–IRS-1 antibody, followed by immunoblotting with antibodies to either phosphotyrosine, the p85 subunit of PI 3-kinase (p85), or the precipitating antibody. (D) The signal from the experiment in C was quantitated by scanning densitometry and the level of phosphotyrosine or PI 3-kinase in each sample was normalized to the level of IRS-1. Note that threefold more PI 3-kinase associated with IRS-1 in cells cultured on BM than in cells cultured on collagen I.