[Frontiers in Bioscience 15, 1018-1022, June 1, 2010]

[Frontiers in Bioscience 15, 1018-1022, June 1, 2010]

Polycomb group proteins are essential for spinal cord development

Chong Wang^1,2, Jian-Jun Zhao^1,2, Cai-Ling Lu², Xu-Dong Han³, Li-Sha An², Xu Ma

1 Graduate school of Peking Union Medical College, Number 5 Dong Dan San Tiao, Beijing 100005, China, 2 Department of Genetics, National Research Institute for Family Planning, 12 Da Hui Si, Beijing 100081, China, 3 The Pathological Department of Zhongguancun Hospital of Beijing city. Number 12 of the zhongguancun south road Haidian Beijing 100190, China

TABLE OF CONTENTS

1. Abstract
2. Introduction
3. Materials and methods: 3.1. Preparation of spina bifida rat model; 3.2. Protein Extraction and Western blot analysis; 3.3. Immunohistochemical detection of H3K27me3 expression
4. Results: 4.1. PcG genes expression changes in the normal spinal cord; 4.2. PcG genes expression changes in the RA-treated spinal cord.
5. Discussion
6. Acknowledgment
7. References

1. ABSTRACT

Birth defects are the leading cause of infantile mortality, followed by neural tube defects (NTD) and congenital heart defects. Spina bifida and anencephaly are among the most common forms of NTD. NTD etiologies are complex, and are associated with both genetic and environmental factors. Polycomb group proteins are essential for vertebrate development; therefore, the purpose of this study was to determine the role of PcGs in spinal cord morphogenesis in normal and all-trans-retinoic acid (RA)-treated fetal rat models of spina bifida. Pregnant rats were gavage-fed RA, resulting in fetal NTD, and embryos were obtained on day 15.5, 17.5, and 19.5. Western blot and immunohistochemistry were used to reveal PcGs expression in the normal and RA-treated E15.5-19.5 rat sacral cords. Western blot and immunohistochemistry revealed decreased EED, RNF2, SUZ12, and H3K27me3 expression in the normal, E15.5-19.5, rat sacral cords. In addition, the spinal cord of RA-treated rats during embryonic development exhibited altered PcGs protein expression. Administration of excess RA results in NTD. Our results suggest that the Polycomb proteins may be involved in spinal cord development.