Methods and compositions for size-controlled homopolymer tailing of substrate polynucleotides by a nucleic acid polymerase

A kit comprising:

• a template-independent nucleic acid polymerase;
• an attenuator polynucleotide comprising an attenuator sequence and a sequence W positioned adjacent to the attenuator sequence, wherein the attenuator sequence is from about 10 nucleotides to about 100 nucleotides in length, and wherein the attenuator polynucleotide comprises a 3′ blocking group selected from the group consisting of at least one ribonucleotide, at least one deoxynucleotide, a C3 spacer, a phosphate, a dideoxynucleotide, an amino group, and an inverted deoxythymidine;
• an adaptor polynucleotide, wherein the adaptor polynucleotide comprises a sequence X which is complementary to sequence W of the attenuator polynucleotide;
• nucleotides complementary to the attenuator sequence;
• and
• a ligase.