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11:31
Generating CRISPR/Cas9 Mediated Monoallelic Deletions to Study Enhancer Function in Mouse Embryonic Stem Cells
Published on: April 2, 2016
Deletion polymorphism of SIGLEC14 and its functional implications.
Masahiro Yamanaka1, Yukinari Kato, Takashi Angata
1Research Center for Medical Glycoscience, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki, Japan.
Glycobiology
|April 17, 2009
Summary
Human Siglec-14, a sialic acid-binding lectin, exhibits varied expression due to a SIGLEC14-SIGLEC5 gene fusion. This genetic variation, prevalent in Asians, may influence immune responses to bacterial infections.
Area of Science:
- Immunology
- Genetics
Background:
- Siglec-14 and Siglec-5 are highly similar sialic acid-binding lectins within the Siglec family.
- Understanding their distinct expression patterns and genetic variations is crucial for immunology research.
Purpose of the Study:
- To investigate the differential expression of Siglec-14 and Siglec-5 in human immune cells.
- To identify the genetic basis for the absence of Siglec-14 expression in certain individuals.
- To explore the functional implications of Siglec-14 in immune response.
Main Methods:
- Development of specific antibodies for Siglec-14 and Siglec-5 detection.
- Analysis of Siglec-14 and Siglec-5 expression on granulocytes, monocytes, and B-cells.
- Genetic analysis to identify gene fusions and allelic frequencies across human populations.
- Functional assays involving forced Siglec-14 expression and lipopolysaccharide stimulation.
Main Results:
- Siglec-14 is expressed on granulocytes and monocytes; Siglec-5 is expressed on granulocytes and B-cells.
- A SIGLEC14-SIGLEC5 gene fusion leads to the absence of Siglec-14 expression in some individuals (SIGLEC14 null phenotype).
- The SIGLEC14 null allele is ancient and shows higher frequency in Asian populations.
- Forced Siglec-14 expression enhanced TNF-alpha secretion in response to lipopolysaccharide.
Conclusions:
- Siglec-14 expression is subject to genetic variation, including a common gene fusion leading to its absence.
- Siglec-14 may play a role in the immune response to bacterial infections, particularly in modulating TNF-alpha secretion.
- The differential expression and genetic distribution of Siglec-14 warrant further investigation in infectious disease contexts.
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