title: miR-326 targets antiapoptotic Bcl-xL and mediates apoptosis in human platelets.
abstract: Platelets play crucial roles in hemostasis, thrombosis, wound healing, inflammation, angiogenesis, and tumor metastases. Because they are anucleated blood cells, platelets lack nuclear DNA, but they do contain mitochondrial DNA, which plays a key role in regulating apoptosis. Recent evidence has suggested that miRNAs are also involved in regulating gene expression and apoptosis in platelets. Our previous study showed that the expression of miR-326 increased visibly when apheresis platelets were stored in vitro. The antiapoptotic Bcl-2 family regulator Bcl-xL has been identified as a putative target of miR-326. In the present study, dual reporter luciferase assays were used to characterize the function of miR-326 in the regulation of the apoptosis of platelet cells. These assays demonstrated that miR-326 bound to the 3'-translated region of Bcl-xL. To directly assess the functional effects of miR-326 expression, levels of Bcl-xL and the apoptotic status of stored apheresis platelets were measured after transfection of miR-326 mimic or inhibitor. Results indicated that miR-326 inhibited Bcl-xL expression and induced apoptosis in stored platelets. Additionally, miR-326 inhibited Bcl-2 protein expression and enhanced Bak expression, possibly through an indirect mechanism, though there was no effect on the expression of Bax. The effect of miR-326 appeared to be limited to apoptosis, with no significant effect on platelet activation. These results provide new insight into the molecular mechanisms affecting differential platelet gene regulation, which may increase understanding of the role of platelet apoptosis in multiple diseases.
authors: The Department of Transfusion Medicine, The Second Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, China; The Department of Transfusion Medicine, The First Affiliated Hospital of the Wenzhou Medical University, Wenzhou, China.
authors: Shifang
authors: S
authors: Yu
authors: School of Basic Medical Sciences, Wenzhou Medical University, Wenzhou, China.
authors: Huicong
authors: H
authors: Huang
authors: The Ningbo Central Blood Station, Ningbo, China.
authors: Gang
authors: G
authors: Deng
authors: The Department of Transfusion Medicine, The First Affiliated Hospital of the Wenzhou Medical University, Wenzhou, China.
authors: Zuoting
authors: Z
authors: Xie
authors: The Department of Transfusion Medicine, The First Affiliated Hospital of the Wenzhou Medical University, Wenzhou, China.
authors: Yincai
authors: Y
authors: Ye
authors: The Department of Transfusion Medicine, The First Affiliated Hospital of the Wenzhou Medical University, Wenzhou, China.
authors: Ruide
authors: R
authors: Guo
authors: The Department of Transfusion Medicine, The First Affiliated Hospital of the Wenzhou Medical University, Wenzhou, China.
authors: Xuejiao
authors: X
authors: Cai
authors: The Department of Transfusion Medicine, The First Affiliated Hospital of the Wenzhou Medical University, Wenzhou, China.
authors: Junying
authors: J
authors: Hong
authors: The Department of Laboratory Medicine, The Third Affiliated Hospital of the Wenzhou Medical University, Ruian, China.
authors: Dingliang
authors: D
authors: Qian
authors: The Department of Transfusion Medicine, The First Affiliated Hospital of the Wenzhou Medical University, Wenzhou, China.
authors: Xiangjing
authors: X
authors: Zhou
authors: The Department of Transfusion Medicine, The Second Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, China.
authors: Zhihua
authors: Z
authors: Tao
authors: The Department of Transfusion Medicine, The First Affiliated Hospital of the Wenzhou Medical University, Wenzhou, China.
authors: Bile
authors: B
authors: Chen
authors: The Department of Laboratory Medicine, The Third Affiliated Hospital of the Wenzhou Medical University, Ruian, China.
authors: Qiang
authors: Q
authors: Li
mesh_terms: D020413:3' Untranslated Regions; D000328:Adult; D017209:Apoptosis / Q000235:genetics*; D001483:Base Sequence; D001781:Blood Component Removal; D001792:Blood Platelets / Q000166:cytology / Q000378:metabolism*; D005260:Female; D005786:Gene Expression Regulation; D017930:Genes, Reporter; D006801:Humans; D008156:Luciferases / Q000235:genetics / Q000378:metabolism; D008297:Male; D035683:MicroRNAs / Q000037:antagonists & inhibitors / Q000235:genetics* / Q000378:metabolism; D008928:Mitochondria / Q000235:genetics* / Q000378:metabolism; D008969:Molecular Sequence Data; D009841:Oligonucleotides / Q000235:genetics / Q000378:metabolism; D061251:Primary Cell Culture; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000235:genetics / Q000378:metabolism; D015398:Signal Transduction; D014162:Transfection; D050998:bcl-2 Homologous Antagonist-Killer Protein / Q000235:genetics / Q000378:metabolism; D051020:bcl-X Protein / Q000235:genetics* / Q000378:metabolism
chemical_list: D020413:3' Untranslated Regions; C494772:BAK1 protein, human; C000595707:BCL2 protein, human; C494811:BCL2L1 protein, human; C545322:MIRN326 microRNA, human; D035683:MicroRNAs; D009841:Oligonucleotides; D019253:Proto-Oncogene Proteins c-bcl-2; D050998:bcl-2 Homologous Antagonist-Killer Protein; D051020:bcl-X Protein; D008156:Luciferases