Developmental changes in the adhesive disk during Giardia differentiation.

Daniel Palm; Malin Weiland; Andrew G McArthur; Jadwiga Winiecka-Krusnell; Michael J Cipriano; Shanda R Birkeland; Sarah E Pacocha; Barbara Davids; Frances Gillin; Ewert Linder; Staffan Svärd

doi:10.1016/j.molbiopara.2005.03.005

PubMed · 15850703

Developmental changes in the adhesive disk during Giardia differentiation.

Daniel Palm·Malin Weiland·Andrew G McArthur·Jadwiga Winiecka-Krusnell·Michael J Cipriano·Shanda R Birkeland·Sarah E Pacocha·Barbara Davids·Frances Gillin·Ewert Linder·Staffan Svärd

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Abstract

Giardia lamblia is a protozoan parasite infecting the upper mammalian small intestine. Infection relies upon the ability of the parasite to attach to the intestine via a unique cytoskeletal organelle, the ventral disk. We determined the composition and structure of the disk throughout the life cycle of the parasite and identified a new disk protein, SALP-1. SALP-1 is an immunodominant protein related to striated fiber-assemblin (SFA). The disk is disassembled during encystation and stored as four fragments in the immobile cyst. Serial Analysis of Gene Expression (SAGE) showed that the mRNA levels of the disk proteins decreased in encystation but two-dimensional protein gels showed that the protein levels were more constant. The parasite emerges without a functional disk but the four disk fragments are quickly reassembled into two new disks on the dividing, early excysting form. Thus, disk proteins are stored within the cyst, ready to be used in the rapid steps of excystation.

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Amino Acid Sequence Animals Electrophoresis, Gel, Two-Dimensional Gene Expression Regulation Gene Expression Regulation, Developmental Giardia lamblia Molecular Sequence Data Morphogenesis Protozoan Proteins RNA, Messenger RNA, Protozoan Sequence Alignment Sequence Homology, Amino Acid Journal Article Research Support, N.I.H., Extramural Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, P.H.S.

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Daniel Palm, Malin Weiland, Andrew G McArthur, Jadwiga Winiecka-Krusnell, Michael J Cipriano, Shanda R Birkeland, Sarah E Pacocha, Barbara Davids, Frances Gillin, Ewert Linder, Staffan Svärd. 2005-03-31. Developmental changes in the adhesive disk during Giardia differentiation.. https://doi.org/10.1016/j.molbiopara.2005.03.005

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