阿拉伯芥ARID-HMG1蛋白與組蛋白去乙醯化酶互作參與非生物逆境反應之功能性研究

Arabidopsis ARID-HMG1 interacts with histone deacetylases in abiotic stress responses

李勇毅(Yung-Yi Lee)

指導教授 ： 吳克強

國立臺灣大學/生命科學院/植物科學研究所/碩士(2014年)

https://doi.org/10.6342/NTU.2014.01777

摘要

在植物細胞中，HMG蛋白是含量第二高的核蛋白家族。阿拉伯芥的16種HMG蛋白可以分為五個類別，ARID-HMG1 (AHMG1)屬於ARID-HMG類別。目前對於ARID-HMG類別蛋白的研究很少，不清楚其在植物體內的功能。在本篇研究中，經由種子萌發率的分析，證明了AHMG1對阿拉伯芥種子的ABA與鹽逆境反應有正調節作用。組蛋白去乙醯化酶 HDA6 是屬於 RPD3 類型的組蛋白去乙醯化酵素。藉由雙螢光互補分析(BiFC)證明了AHMG1可以和HDA6相互作用;此外，AHMG1和HDA6都參與鹽逆境反應基因RD22和RD29B的正調控。這些結果表明AHMG1可能和HDA6共同促進阿拉伯芥對鹽逆境的抵抗。同時，我們發現AHMG1可能間接促進FLC基因的表現，進而造成對開花時間的抑制。綜合以上結果， AHMG1蛋白對於非生物性逆境反應以及植物開花都扮演著重要的角色。

關鍵字

阿拉伯芥 ； 組蛋白去乙醯酶 ； AHMG1 ； 非生物逆境 ； 開花

並列摘要

High mobility group (HMG) box containing proteins are the second most abundant nuclear protein family in plant cells. There are 16 HMG proteins which can be classified into 5 classes in Arabidopsis. ARID-HMG1 (AHMG1) belongs to the ARID-HMG class. The function of AHMG1 in plant cells is still unknown. In this study, we found that AHMG1 positively regulates the ABA and salt stress response. Histone deacetylase 6 (HDA6) is a RPD3-type histone deacetylase, and is known to participate in plant salt stress response. Bimolecular fluorescence complementation assay showed that HDA6 interacts with AHMG1. The expression of salt stress response genes was decreased in hda6 and ahmg1-2 mutants under abscisic acid ABA and salt stress. These results support that AHMG1 may interact with HDA6 in abiotic stress response. Furthermore, AHMG1 also regulates Arabidopsis flowering time through the repression of flowering gene FLC expression. Thus, AHMG1 plays important roles in Arabidopsis abiotic stress response and flowering control.

並列關鍵字

Arabidopsis ； AHMG1 ； abiotic stress ； histone deacetylases ； flowering

參考文獻

Antosch, M., Mortensen, S.A., and Grasser, K. D. (2012). Plant proteins containing high mobility group box DNA-binding domains modulate different nuclear processes. Plant Physiol. 159: 875–883.

Berger, S.L. (2007). The complex language of chromatin regulation during transcription. Nature 447: 407–412.

Bustin, M. (2001). Revised nomenclature for high mobility group (HMG) chromosomal proteins. Trends Biochem. Sci. 26: 152-153.

Bustin, M., and Reeves, R. (1996). High-mobility-group chromosomal proteins: architectural components that facilitate chromatin function. Prog. Nucleic Acids Res. Mol. Bol. 54: 35–100.

Chen, L.T., Luo, M., Wang, Y.Y., and Wu, K. (2010). Involvement of Arabidopsis histone deacetylase HDA6 in ABA and salt stress response. J. Exp. Bot. 61: 3345–3353.