Table 1.

Classification of integration junctions in the presence and absence of restriction enzymes

Linearizing enzyme	Co-transformation enzymeb	Relative frequency of integrationc	Fold increase in integration	Junctions			Length of microhomology (bp)d
				Total	REMI mediatede	NHI	5	4	3	2	0–1
BamHI	–	2.1 ± 0.1	–	14	0	14	0	0	7	1	6
EcoRI	–	1.1 ± 0.1	–	8	0	8	0	0	3	1	4
KpnI	–	1.8 ± 0.4	–	14	0	14	0	1	1	5	7
Controla				36	0	36	0	1	11	7	17
BamHI	BamHI	11.5 ± 0.7	5.5 ± 1.2**	8	7	1	0	1	0	0	0
SalI	BglII	10.8 ± 2.1	8.3 ± 1.2**	18	16	2	0	1	0	1	0
EcoRI	BglII′	3.2 ± 0.3	2.9 ± 0.3**	8	4	4	1	1	1	0	1
KpnI	BglII	4.3 ± 0.8	2.4 ± 0.8**	14	0	14	3	1	2	1	7
Asp718	KpnI	5.8 ± 0.8	2.3 ± 0.3**	22	6	16	0	2	2	5	7
Asp718 filled	KpnI	3.26 ± 0.56	1.4**	8	4	4	0	2	0	1	1
Total				78	37	41	4	8	5	8	16

^aIn the control, the BamHI or EcoRI-linearized YIplac211 or the KpnI-linearized pM150 plasmid was transformed into RSY12 without addition of restriction enzyme. The junction sequences which resulted are shown in Figures 1 and 4 in ref. (3) (BamHI and EcoRI-linearized YIplac211) and Figure 4A (KpnI-linearized pM150).

^bFor example, in the combination of BamHI and BamHI, BamHI-linearized pM150 plasmid was transformed into RSY12 in the presence of BamHI. In the combination of SalI and BglII, SalI-linearized pM150 plasmid was transformed into RSY12 in the presence of BglII. The KpnI-BglII junction sequences are shown in Figure 4B and the junction sequences of other restriction enzymes-induced integration events are shown in Figure 3.

^cData are taken from ref. (1). Number of integration events per microgram of DNA per 10⁴ 2 μm transformants. This number represents the average of five of more experiments ± the standard error. **, t-test indicates a statistically significant difference (P < 0.05) from control values.

^dNumber of bases at the ends of integrating plasmid DNA which is homologous to the genomic target sequences.

^eREMI stands for restriction enzyme-mediated integration.