通过像素值准确分析聚丙烯酰胺凝胶电泳DNA片段大小的方法  

Accurate Analysis of DNA Size on Polyacrylamide Gel Electrophoresis by Its Pixel

作　　者：张波[1] 刘林[1] 兰茗清[1] 杨静[1] 查友贵[1] 赵婧[1] 李成云[1] 

机构地区：[1]云南农业大学植物保护学院,农业生物多样性与病虫害控制教育部重点实验室,农业生物多样性应用技术国家工程研究中心,云南昆明650201

出　　处：《云南农业大学学报（自然科学版）》2013年第5期741-744,共4页Journal of Yunnan Agricultural University:Natural Science

基　　金：公益性行业(农业)科研专项(200903035-07);国家"973"项目(2013CB127700);云南省自然科学基金重点项目(2009CC004)

摘　　要：利用聚丙烯酰胺凝胶电泳对PCR产物进行分离是一项基础性的、常用实验技术，但根据DNA在聚丙烯酰胺凝胶电泳上距离读出目的DNA片段大小的方法尚未见报道。本文首次探讨了DNA聚丙烯酰胺凝胶电泳条带的像素与其条带之间大小的关系，使用SPSS对条带对应的像素值和对应的条带大小进行了线性函数、二次多项式、复合函数、增长函数、对数函数、三次多项式、S型曲线、指数函数、倒数（反比例）函数、幂函数和logistic函数11种函数的拟合分析，结果表明：条带对应的像素值与其对应条带的大小相关系数均达0．950以上的函数主要有复合函数、增长函数、三次多项式、指数函数、倒数函数、幂函数和logistic函数，其中相关性最好的是logistic函数，其相关系数为0．998；而且，通过logistic函数算出的7条目标条带的测算值与实际DNA片段的值最接近，各片段大小的测算值与实际片段大小仅相差5—17bp。以上结果表明，logis．tic函数能够较准确的放映出经聚丙烯酰胺凝胶电泳后DNA的像素值与其片段大小之间的关系。这将有利于开发出电泳后直接读取DNA片段大小的软件。The technique of PCR products separated by polyacrylamide gel electrophoresis is the basic and frequentlyused in molecular experiment. At present, it has not been reported that the size of PCR products was calculated by DNA ladder marker and measuring distance of different DNA electrophoretic band on the polyaerylamide gel electrophoresis. In this paper, it was first reported the relationship be tween the pixel of DNA electrophoretic band on polyacrylamide gel electrophoresis and its size. It was carried on eleven functions （linear function, quadratic polynomial, function of function, growth func tion, logarithmic function, cubic polynomial, sigrnoid curve, exponential function, reciprocal function, power function and logistic function） fitting analysis about relationship between the DNA electrophoresisbands and their size by the SPSS software. The results showed that coefficient of association between the pixel of DNA bands and their sizes was more than 0. 950 in the function of function, growth function, cu bic polynomial, exponential function, reciprocal function, power function and logistic function, and the correlation coefficient of logistic function was the best, i. e. 0. 998. The seven DNA bands calculated by logistic function were the closest the actual DNA size （ 100, 200, 300, 400, 500, 700, 1 000 bp）, there were only 5 17 bp apart. Above all, logistic function could accurately show the relationship be tween pixel of DNA electrophoretic band on the polyacrylamide gel electrophoresis and its size. It is ad vantaged to exploit software directly acquired DNA size after electrophoresis.

关 键 词：聚丙烯酰胺凝胶电泳 DNA片段大小 像素 logistic函数 

分 类 号：Q754[生物学—分子生物学]