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Isolation of Primary Myofibroblasts from Mouse and Human Colon Tissue
Published on: October 12, 2013
Brush border myosin I (BBMI): a basally localized transcript in human jejunal enterocytes
1Division of Pediatric Gastroenterology/Nutrition, The Floating Hospital for Children, New England Medical Center Hospitals, Boston, Massachusetts 02111, USA.
Summary
Researchers investigated the localization of brush border myosin I (BBMI) and intestinal fimbrin (I-fim) mRNAs in human enterocytes. BBMI mRNA showed basal localization, suggesting new pathways for cytoskeletal protein sorting.
Area of Science:
- Cell Biology
- Molecular Biology
- Gastroenterology
Background:
- Villin mRNA, encoding an apical microvillous protein, exhibits dichotomous localization in the basal region of human enterocytes.
- Understanding the localization mechanisms of other microvillous cytoskeletal proteins is crucial for elucidating cellular organization.
Purpose of the Study:
- To examine the mRNA localization of brush border myosin I (BBMI) and intestinal fimbrin (I-fim) in human enterocytes.
- To clone a full-length cDNA for BBMI to facilitate studies on mRNA targeting mechanisms.
Main Methods:
- In situ hybridization was employed to determine the cellular localization of BBMI and I-fim mRNAs.
- A full-length cDNA for BBMI, including 5' and 3' untranslated regions (UTRs), was cloned.
Main Results:
- BBMI mRNA was found to be localized to the basal region of human enterocytes.
- I-fim mRNA displayed a diffuse distribution within the enterocytes.
- The cloned BBMI cDNA showed high sequence identity with bovine and rat homologs but lacked similarity in 3'-UTRs with villin.
Conclusions:
- The basal localization of BBMI mRNA suggests specific sorting pathways for intestinal microvillous cytoskeletal proteins.
- This study provides evidence for novel mechanisms governing the spatial organization of enterocyte components.
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