水牛ABCD基因家族生物信息学分析及ABCD1基因表达研究

Bioinformatics Analysis of ABCD Gene Family in Buffalo and Expression Analysis of ABCD1 Gene

为鉴定水牛ATP结合盒(ATP-binding cassette,ABC)转运蛋白D(ABCD)基因家族成员及其在水牛中的表达,本研究利用生物信息学对水牛ABCD基因家族的染色体定位、基因结构、保守结构域、蛋白理化性质进行分析,利用实时荧光定量PCR检测ABCD1基因在水牛各组织及不同泌乳期乳腺中的表达,并用3种激素处理水牛乳腺上皮细胞,检测激素对ABCD1基因表达的影响。结果显示,从水牛全基因组中共鉴定出9个ABCD家族基因,分别为ABCD1、ABCD2、ABCD3、ABCD4,其中ABCD4基因包含6个不同转录本(ABCD4X1-ABCD4X6),ABCD1~ABCD44个基因分别位于X、4、6、11号染色体;序列分析发现,ABCD家族基因包含9~22个内含子,编码444~741个氨基酸,分子质量为49.63~83.41 ku,等电点为6.43~9.64;共找到ABC_membrane_2、Endonuclease_5、ABC_tran 3个ABCD家族基因所共有的功能基序。ABCD基因家族可分为4个亚族,系统进化树显示,ABCD基因高度保守。共线性分析表明,水牛和奶牛之间存在7对直系同源的ABCD家族基因。不同组织定量表达结果表明,ABCD1基因在水牛15个组织中均有表达,其中在脂肪组织中表达量最高。不同泌乳时期的乳腺组织定量表达结果显示,ABCD1基因在50 d表达量达到最高,整个泌乳期呈现低-高-低表达模式。用不同浓度催乳素、雌二醇、孕酮分别处理水牛乳腺细胞,当催乳素、雌二醇和孕酮浓度分别达到2.0、0.3和4.5μg/mL以上时,ABCD1基因表达量显著高于对照组。结果表明,水牛ABCD基因家族包含9个基因,其中ABCD1基因参与泌乳调控,本研究为进一步探讨ABCD家族基因在水牛乳腺中的功能提供了参考依据。

This study was aimed to indentify the members of ATP-binding cassette(ABC)transporter D(ABCD)gene and its expression in buffalo.The chromosome mapping,gene structure,conserved domains and physicochemical properties of ABCD gene family in buffalo were analyzed using bioinformatics.The expression of ABCD1 gene in buffalo tissues and mammary glands at different lactation stages was detected by Real-time quantitative PCR.The effects of 3 hormones on the expression of ABCD1 gene in mammary epithelial cells of buffalo were also detected.The results indicated that 9 ABCD gene were identified from the whole genome of buffalo,which included ABCD1,ABCD2,ABCD3 and ABCD4,and ABCD4 gene contained 6 different transcripts(ABCD4X1-ABCD4X6).ABCD1-ABCD4 were identified on chromosome X,4,6 and 11,respectively.ABCD gene included 9-22 introns,which coded 444-741 amino acid residues with the molecular weight ranging from 49.63-83.41 ku,and the isoelectric points ranging from 6.43-9.64.3 motifs were identified from ABCD protein,including ABC_membrane_2,Endonuclease_5 and ABC_tran.ABCD gene family could be divided into 4 subfamilies,and the evolutionary tree of different species showed that ABCD gene was highly conserved.Collinearity analysis results showed that there were 7 pairs of ABCD gene family with homologous lineages between buffalo and cattle.ABCD1 gene was expressed in 15 tissues of buffalo with a relatively high level in fat.The expression of ABCD1 gene was variable during lactation and exhibited a trend of low-high-low with the highest level at 50 days after parturition.The mammary gland cells in buffalo were treated with different concentrations of prolactin,estradiol and progesterone,the expression of ABCD1 gene was significantly higher than that of control group when the concentrations of prolactin,estradiol and progesterone were above 2.0,0.3 and 4.5μg/mL,respectively.The results showed that there were 9 genes in ABCD gene family of buffalo,among which ABCD1 gene was involved in the regulation of lactation.This study provided a reference for further exploring the function of ABCD family genes in mammary gland of buffalo.