Effects of protein kinase a phosphorylation on the biochemical properties and subcellular location of human choline kinase beta
Choline kinase is the most upstream enzyme in the CDP-choline pathway. It catalyzes the phosphorylation of choline to phosphorylcholine in the presence of ATP and Mg2+ during the biosynthesis of phosphatidylcholine, the major phospholipid in eukaryotic cell membranes. In humans, choline kinase (C...
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| Format: | Monograph |
| Language: | English |
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Pusat Pengajian Kesihatan
2016
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| Online Access: | http://eprints.usm.my/59805/1/PROF%20MADYA%20DR%20SEE%20TOO%20WEI%20CUN%20-%20e.pdf |
| _version_ | 1797014347364433920 |
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| author | Cun, See Too Wei |
| author_facet | Cun, See Too Wei |
| author_sort | Cun, See Too Wei |
| collection | USM |
| description | Choline kinase is the most upstream enzyme in the CDP-choline
pathway. It catalyzes the phosphorylation of choline to phosphorylcholine in the
presence of ATP and Mg2+ during the biosynthesis of phosphatidylcholine, the
major phospholipid in eukaryotic cell membranes. In humans, choline kinase (CK)
is encoded by two separate genes, cka and ckp, which produce three isoforms,
CKa1, CKa2, and CKp. Previous studies have associated ckp with muscle
development; however, the molecular mechanism underlying the transcriptional
regulation of ckp has never been elucidated. In this report, the distal promoter region of the
ckp gene was characterized. Mutational analysis of the promoter sequence and
electrophoretic mobility shift assays (EMSA) showed that Ets and GATA
transcription factors were essential for the repression of ckp promoter activity.
Supershift and chromatin immunoprecipitation (ChIP) assays further identified that
GATA3 but not GATA2 was bound to the GATA site of ckp promoter. In addition,
phorbol-12-myristate-13-acetate (PMA) decreased ckp promoter activity through
Ets and GATA elements. PMA also decreased the ckp mRNA and protein levels
about 12 hours after the promoter activity was down-regulated. EMSA further
revealed that PMA treatment increased the binding of both Ets and GATA
transcription factors to their respective DNA elements. The PMA-mediated
repressive effect was abolished by chronic PMA treatment and by treatment with
the PKC inhibitor PKC412, but not the PKC inhibitor Go 6983, suggesting PKCe or
PKCq as the PKC isozyme involved in the PMA-mediated repression of ckp
promoter. Further confirmation by using PKC isozyme specific inhibitors identified
PKCe as the isozyme that mediated the PMA repression of ckp promoter. |
| first_indexed | 2024-04-09T03:52:47Z |
| format | Monograph |
| id | usm.eprints-59805 |
| institution | Universiti Sains Malaysia |
| language | English |
| last_indexed | 2024-04-09T03:52:47Z |
| publishDate | 2016 |
| publisher | Pusat Pengajian Kesihatan |
| record_format | dspace |
| spelling | usm.eprints-598052024-03-27T07:24:28Z http://eprints.usm.my/59805/ Effects of protein kinase a phosphorylation on the biochemical properties and subcellular location of human choline kinase beta Cun, See Too Wei R Medicine RC31-1245 Internal medicine Choline kinase is the most upstream enzyme in the CDP-choline pathway. It catalyzes the phosphorylation of choline to phosphorylcholine in the presence of ATP and Mg2+ during the biosynthesis of phosphatidylcholine, the major phospholipid in eukaryotic cell membranes. In humans, choline kinase (CK) is encoded by two separate genes, cka and ckp, which produce three isoforms, CKa1, CKa2, and CKp. Previous studies have associated ckp with muscle development; however, the molecular mechanism underlying the transcriptional regulation of ckp has never been elucidated. In this report, the distal promoter region of the ckp gene was characterized. Mutational analysis of the promoter sequence and electrophoretic mobility shift assays (EMSA) showed that Ets and GATA transcription factors were essential for the repression of ckp promoter activity. Supershift and chromatin immunoprecipitation (ChIP) assays further identified that GATA3 but not GATA2 was bound to the GATA site of ckp promoter. In addition, phorbol-12-myristate-13-acetate (PMA) decreased ckp promoter activity through Ets and GATA elements. PMA also decreased the ckp mRNA and protein levels about 12 hours after the promoter activity was down-regulated. EMSA further revealed that PMA treatment increased the binding of both Ets and GATA transcription factors to their respective DNA elements. The PMA-mediated repressive effect was abolished by chronic PMA treatment and by treatment with the PKC inhibitor PKC412, but not the PKC inhibitor Go 6983, suggesting PKCe or PKCq as the PKC isozyme involved in the PMA-mediated repression of ckp promoter. Further confirmation by using PKC isozyme specific inhibitors identified PKCe as the isozyme that mediated the PMA repression of ckp promoter. Pusat Pengajian Kesihatan 2016 Monograph NonPeerReviewed application/pdf en http://eprints.usm.my/59805/1/PROF%20MADYA%20DR%20SEE%20TOO%20WEI%20CUN%20-%20e.pdf Cun, See Too Wei (2016) Effects of protein kinase a phosphorylation on the biochemical properties and subcellular location of human choline kinase beta. Project Report. Pusat Pengajian Kesihatan. (Submitted) |
| spellingShingle | R Medicine RC31-1245 Internal medicine Cun, See Too Wei Effects of protein kinase a phosphorylation on the biochemical properties and subcellular location of human choline kinase beta |
| title | Effects of protein kinase a phosphorylation on
the biochemical properties and subcellular
location of human choline kinase beta |
| title_full | Effects of protein kinase a phosphorylation on
the biochemical properties and subcellular
location of human choline kinase beta |
| title_fullStr | Effects of protein kinase a phosphorylation on
the biochemical properties and subcellular
location of human choline kinase beta |
| title_full_unstemmed | Effects of protein kinase a phosphorylation on
the biochemical properties and subcellular
location of human choline kinase beta |
| title_short | Effects of protein kinase a phosphorylation on
the biochemical properties and subcellular
location of human choline kinase beta |
| title_sort | effects of protein kinase a phosphorylation on the biochemical properties and subcellular location of human choline kinase beta |
| topic | R Medicine RC31-1245 Internal medicine |
| url | http://eprints.usm.my/59805/1/PROF%20MADYA%20DR%20SEE%20TOO%20WEI%20CUN%20-%20e.pdf |
| work_keys_str_mv | AT cunseetoowei effectsofproteinkinaseaphosphorylationonthebiochemicalpropertiesandsubcellularlocationofhumancholinekinasebeta |