Figure 2

The expected construction of cDNA insertion and all types of Restriction Enzyme Cutting Abnormality (RECA). The label “Expected” means the expected construction of cDNA library. Sequencing direction is indicated as 3′ or 5′ with an arrow. VF1 (Vector fragment 1) and VF2 (Vector fragment 2) are referred to the left and right vector borders of the cloning sites. A, B, C, D, E and F are special types of RECA, defined as following: RECA-Type A: EcoRI site is cut off but XhoI site remains intact. A1: cDNA is inserted with inversion; A2: cDNA is inserted without inversion; A3: Adapter/linker fragments are inserted. RECA-Type B: XhoI site is cut off but EcoRI site remains intact. B1: cDNA is inserted with inversion; B2: cDNA is inserted without inversion. RECA-Type C: Neither of the two enzyme sites is cut off. RECA-Type D: Both the two enzyme sites are cut off, but the excised vector fragment remains. RECA-Type E: XhoI cuts off the vector at wrong site. RECA-Type F: EcoRI cuts off the vector at wrong site. The yellow color indicates EcoRI recognition site or EcoRI sticky end. The brown color stands for XhoI recognition site or XhoI sticky end. The blue represents the plasmid vector. Dark green denotes for adapter/linker fragment. cDNA insert direction is represented by red color with gradual changes: cDNA sense strand is from deep red to light red whereas cDNA non-sense strand is from light red to deep red.