upSET, the Drosophila homologue of SET3, Is Required for Viability and the Proper Balance of Active and Repressive Chromatin Marks
Chromatin plays a critical role in faithful implementation of gene expression programs. Different post-translational modifications (PTMs) of histone proteins reflect the underlying state of gene activity, and many chromatin proteins write, erase, bind, or are repelled by, these histone marks. One su...
| Main Authors: | , , , , , |
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| Format: | Article |
| Language: | English |
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Oxford University Press
2017-02-01
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| Series: | G3: Genes, Genomes, Genetics |
| Subjects: | |
| Online Access: | http://g3journal.org/lookup/doi/10.1534/g3.116.037788 |
| _version_ | 1819149749697118208 |
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| author | Kyle A. McElroy Youngsook L. Jung Barry M. Zee Charlotte I. Wang Peter J. Park Mitzi I. Kuroda |
| author_facet | Kyle A. McElroy Youngsook L. Jung Barry M. Zee Charlotte I. Wang Peter J. Park Mitzi I. Kuroda |
| author_sort | Kyle A. McElroy |
| collection | DOAJ |
| description | Chromatin plays a critical role in faithful implementation of gene expression programs. Different post-translational modifications (PTMs) of histone proteins reflect the underlying state of gene activity, and many chromatin proteins write, erase, bind, or are repelled by, these histone marks. One such protein is UpSET, the Drosophila homolog of yeast Set3 and mammalian KMT2E (MLL5). Here, we show that UpSET is necessary for the proper balance between active and repressed states. Using CRISPR/Cas-9 editing, we generated S2 cells that are mutant for upSET. We found that loss of UpSET is tolerated in S2 cells, but that heterochromatin is misregulated, as evidenced by a strong decrease in H3K9me2 levels assessed by bulk histone PTM quantification. To test whether this finding was consistent in the whole organism, we deleted the upSET coding sequence using CRISPR/Cas-9, which we found to be lethal in both sexes in flies. We were able to rescue this lethality using a tagged upSET transgene, and found that UpSET protein localizes to transcriptional start sites (TSS) of active genes throughout the genome. Misregulated heterochromatin is apparent by suppressed position effect variegation of the wm4 allele in heterozygous upSET-deleted flies. Using nascent-RNA sequencing in the upSET-mutant S2 lines, we show that this result applies to heterochromatin genes generally. Our findings support a critical role for UpSET in maintaining heterochromatin, perhaps by delimiting the active chromatin environment. |
| first_indexed | 2024-12-22T14:06:33Z |
| format | Article |
| id | doaj.art-6dee3ba5e52440698128c2ae39953585 |
| institution | Directory Open Access Journal |
| issn | 2160-1836 |
| language | English |
| last_indexed | 2024-12-22T14:06:33Z |
| publishDate | 2017-02-01 |
| publisher | Oxford University Press |
| record_format | Article |
| series | G3: Genes, Genomes, Genetics |
| spelling | doaj.art-6dee3ba5e52440698128c2ae399535852022-12-21T18:23:18ZengOxford University PressG3: Genes, Genomes, Genetics2160-18362017-02-017262563510.1534/g3.116.03778826upSET, the Drosophila homologue of SET3, Is Required for Viability and the Proper Balance of Active and Repressive Chromatin MarksKyle A. McElroyYoungsook L. JungBarry M. ZeeCharlotte I. WangPeter J. ParkMitzi I. KurodaChromatin plays a critical role in faithful implementation of gene expression programs. Different post-translational modifications (PTMs) of histone proteins reflect the underlying state of gene activity, and many chromatin proteins write, erase, bind, or are repelled by, these histone marks. One such protein is UpSET, the Drosophila homolog of yeast Set3 and mammalian KMT2E (MLL5). Here, we show that UpSET is necessary for the proper balance between active and repressed states. Using CRISPR/Cas-9 editing, we generated S2 cells that are mutant for upSET. We found that loss of UpSET is tolerated in S2 cells, but that heterochromatin is misregulated, as evidenced by a strong decrease in H3K9me2 levels assessed by bulk histone PTM quantification. To test whether this finding was consistent in the whole organism, we deleted the upSET coding sequence using CRISPR/Cas-9, which we found to be lethal in both sexes in flies. We were able to rescue this lethality using a tagged upSET transgene, and found that UpSET protein localizes to transcriptional start sites (TSS) of active genes throughout the genome. Misregulated heterochromatin is apparent by suppressed position effect variegation of the wm4 allele in heterozygous upSET-deleted flies. Using nascent-RNA sequencing in the upSET-mutant S2 lines, we show that this result applies to heterochromatin genes generally. Our findings support a critical role for UpSET in maintaining heterochromatin, perhaps by delimiting the active chromatin environment.http://g3journal.org/lookup/doi/10.1534/g3.116.037788Drosophilachromatinheterochromatinposition effect variegationupSETSET3MLL5 |
| spellingShingle | Kyle A. McElroy Youngsook L. Jung Barry M. Zee Charlotte I. Wang Peter J. Park Mitzi I. Kuroda upSET, the Drosophila homologue of SET3, Is Required for Viability and the Proper Balance of Active and Repressive Chromatin Marks G3: Genes, Genomes, Genetics Drosophila chromatin heterochromatin position effect variegation upSET SET3 MLL5 |
| title | upSET, the Drosophila homologue of SET3, Is Required for Viability and the Proper Balance of Active and Repressive Chromatin Marks |
| title_full | upSET, the Drosophila homologue of SET3, Is Required for Viability and the Proper Balance of Active and Repressive Chromatin Marks |
| title_fullStr | upSET, the Drosophila homologue of SET3, Is Required for Viability and the Proper Balance of Active and Repressive Chromatin Marks |
| title_full_unstemmed | upSET, the Drosophila homologue of SET3, Is Required for Viability and the Proper Balance of Active and Repressive Chromatin Marks |
| title_short | upSET, the Drosophila homologue of SET3, Is Required for Viability and the Proper Balance of Active and Repressive Chromatin Marks |
| title_sort | upset the drosophila homologue of set3 is required for viability and the proper balance of active and repressive chromatin marks |
| topic | Drosophila chromatin heterochromatin position effect variegation upSET SET3 MLL5 |
| url | http://g3journal.org/lookup/doi/10.1534/g3.116.037788 |
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