Expansion and diversification of the SET domain gene family following whole-genome duplications in Populus trichocarpa

Table 2 Estimated dates of the duplication events leading to pairs of SET genes in Populus and Arabidopsis

Species	Duplicated pair		Number of anchors	Mean K_s	SD K_s	Estimated time (Mya)
Populus	Suvh2	Suvh9	777	0.2674	0.0922	14.69
	Suvh3	Suvh10	84	0.2841	0.1030	15.61
	Suvh4b	Suvh4c	14	0.2566	0.0642	14.10
	Suvh7	Suvh1	105	0.2597	0.0715	14.27
	Suvr1	Suvr2	176	0.283	0.0956	15.55
	Suvr4a	Suvr4b	15	0.2898	0.0978	15.93
	Suvr5a	Suvr5b	19	0.2686	0.0968	14.76
	Atxr5a	Atxr5b	118	0.2737	0.0927	15.04
	Atxr6a	Atxr6b	46	0.2657	0.0875	14.60
	Ashh2a	Ashh2b	381	0.2683	0.0894	14.74
	Ashh4	Ashh3	16	0.2568	0.0723	14.11
	Atxr3a	Atxr3b	109	0.2758	0.0877	15.15
	Clfa	Clfb	29	0.2844	0.0966	15.62
	Swna	Swnb	394	0.2697	0.0842	14.82
	Atx1	Atx2	11	0.2483	0.0665	13.64
	Atx3a	Atx3b	394	0.2697	0.0842	14.82
	Atx4	Atx5	46	0.2657	0.0875	14.60
	Atxr7a	Atxr7b	566	0.2517	0.0548	13.83
	Setd2a	Setd2b	1034	0.2594	0.0583	14.09
	Atx4/5	Atx3a/b	46	1.5129	0.1836	83.13
Arabidopsis	SUVH3	SUVH7	177	0.8413	0.2201	28.04
	SUVR2	SUVR1	33	0.8419	0.2180	28.06
	SWN	MEA	41	0.8182	0.1871	27.27
	ATX1	ATX2	113	0.8635	0.2162	28.78
	ASHH4	ASHH3	138	0.8422	0.2319	28.07

The mean K_s value was calculated for each pair of protein-coding genes within a duplicated block and used to date the duplication events. K_s values of all duplicated gene pairs greater than 1.5 and less than 0.5 were discarded for Arabidopsis; K_s greater than 0.4 for Populus was also discarded, except Atx4/5 and Atx3a/b

ISSN: 2730-7182