Histone H3S10 phosphorylation by the JIL-1 kinase in pericentric heterochromatin and on the fourth chromosome creates a composite H3S10phK9me2 epigenetic mark

The JIL-1 kinase mainly localizes to euchromatic interband regions of polytene chromosomes and is the kinase responsible for histone H3S10 phosphorylation at interphase in Drosophila. However, recent findings raised the possibility that the binding of some H3S10ph antibodies may be occluded by the H3K9me2 mark obscuring some H3S10 phosphorylation sites. Therefore, we have characterized an antibody to the epigenetic H3S10phK9me2 double mark as well as three commercially available H3S10ph antibodies. The results showed that for some H3S10ph antibodies their labeling indeed can be occluded by the concomitant presence of the H3K9me2 mark. Furthermore, we demonstrate that the double H3S10phK9me2 mark is present in pericentric heterochromatin as well as on the fourth chromosome of wild-type polytene chromosomes but not in preparations from JIL-1 or Su(var)3-9 null larvae. Su(var)3-9 is a methyltransferase mediating H3K9 dimethylation. Furthermore, the H3S10phK9me2 labeling overlapped with that of the non-occluded H3S10ph antibodies as well as with H3K9me2 antibody labeling. Interestingly, when a Lac-I-Su(var)3-9 transgene is overexpressed, it upregulates H3K9me2 dimethylation on the chromosome arms creating extensive ectopic H3S10phK9me2 marks suggesting that the H3K9 dimethylation occurred at euchromatic H3S10ph sites. This is further supported by the finding that under these conditions euchromatic H3S10ph labeling by the occluded antibodies was abolished. Thus, our findings indicate a novel role for the JIL-1 kinase in epigenetic regulation of heterochromatin in the context of the chromocenter and fourth chromosome by creating a composite H3S10phK9me2 mark together with the Su(var)3-9 methyltransferase.     

基于生态系统服务功能和生态敏感性的自然生态空间管制分区研究

自然生态空间分区管制是国土空间管制的重要组成部分,也是国内外生态环境研究的热点。针对国内自然生态空间用途管制暂处于试点阶段,有关管制的方法有待进一步探究的情况下,旨在通过江西省自然生态空间管制分区,为实现合理保护自然生态资源,促进自然生态系统健康有序发展提供参考。以江西省为研究对象,借助GIS空间分析技术,通过生态系统服务功能重要性和生态敏感性评价,构建二维关联判断矩阵,进行自然生态空间管制分区,并以此提出相关的管制建议。结果表明:江西省自然生态空间总面积为117924.67 km~2,约占全省总面积的70.66%,从空间上可划分为高重要高敏感区、中度重要敏感区和低重要低敏感区3种类型区;其中,高重要高敏感区以生态保护和生态修复为主,实施严格的区域准入措施;中度重要敏感区可依托区域生态资源优势,合理开展以维护、改善生态系统服务功能为主要目的生态经营活动;低重要低敏感区允许在不破坏生态系统结构和功能的前提下,适度开展一定规模的生产建设活动,减少污染排放,增强区域生态功能。全省16个国家自然保护区基本位于高重要高敏感范围内。基于生态系统服务功能与生态敏感性的自然生态空间管制分区可以为自然生态空间管制提供新思路,从而有效推动管制工作的进行。