The Gene Gateway Workbook

U.S. Department of Energy Office of Science Updated: 10/05/2004
The Importance of the Primary Citation
To understand what you are really looking at in this structure, you would need to access
the article listed as the primary citation. Although the full text for some articles may be
freely available online, most articles are accessible only through a university library that
provides public access to its collections. Sometimes you can purchase a copy of the
article online from the publisher.
The article for this structure has been accessed, and here are some of the main points
to understand about this structure:
• Only the soluble portion of the HFE polypeptide chain is included in the
1A6Z structure. The transmembrane domain of the HFE protein is missing.
This structure has only 275 of the 348 amino acids in the complete HFE
protein sequence.
• The first 22 amino acids of the HFE polypeptide sequence have been left
out because they are not part of the mature, functional protein. Therefore,
the first amino acid in this structure is really the 23 rd , and cysteine 260 is the
cysteine residue involved in the C282Y mutation that we learned about in
Activity #1.
• Each HFE polypeptide chain is complexed with another polypeptide chain
called beta-2 microglobulin.
• The 1A6Z structure consists of two separate molecules of the HFE/beta-2
microglobulin complex.
Gene Gateway: A Web Companion to the Human Genome Landmarks Poster
www.DOEgenomes.org/genegateway
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