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The construction, identification and partial characterization of plasmids containing guinea-pig milk protein complementary DNA sequences.

ABSTRACT: A complementary DNA (cDNA) plasmid library has been constructed in the plasmid pAT153, using poly(A)-containing RNA isolated from the lactating guinea-pig mammary gland as the starting material. Double stranded cDNA was inserted into the EcoRI site of the plasmid using poly(dA . dT) tails, then transformed into Escherichia coli HB101. From the resulting colonies we have selected and partially characterized plasmids containing cDNA copies of the mRNAs for casein A, casein B, casein C and alpha-lactalbumin. However, the proportion containing casein C cDNA was exceptionally low, and these contained at best 60% of the mRNA sequence.

SUBMITTER: Craig RK

PROVIDER: S-EPMC1162837 | biostudies-other | 1981 Mar

REPOSITORIES: biostudies-other

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