Genome-wide identification, characterization and expression analysis of populusleucine-rich repeat receptor-like protein kinase genes

Table 1 Group and subgroup designations of LRR-RLK proteins from Populus trichocarpa

Groups	Subgroups	Gene number	PI	MW(kDa)	aa length	With signal peptide	Homologous Arabidopsisgenes based on LRR
I	a	16	5.29-7.94	43.32-104.52	391-934	56.3%	FRK1, IOS1, MEE39
I	b	17	5.24-8.86	49.58-101.98	455-923	58.8%	FEI1-2, TMKL1
II		29	5.19-9.45	68.92-79.48	564-715		NIK1, NIK2, SARK,NIK3, SERK1-5, MRH1
III		29	5.85-9.19	59.07-74.62	547-684	65.5%	RLK902, RKL1, RUL1, PRK2A
IV		20	5.43-8.66	59.51-132.35	546-1211		IMK2, IMK3
V		11	5.82-8.03	67.75-86.62	625-794	54.6%	SRF1-8, SCM
VI		16	5.68-9.21	74.95-114.81	673-1072
VII	a	6	5.22-8.72	74.08-133.71	673-1221	83.3%
VII	b	30	6.11-8.67	66.14-128.21	599-1162	30.0%	*Populus* -specific
VIII		17	5.29-8.16	48.97-106.77	449-978	58.8%
IX		12	5.31-6.68	98.97-103.46	908-949	100%
X		29	5.22-8.77	49.72-130.50	446-1205	82.8%	BIR1, PSKR2, PSKR1,BRL2, BRI1, BRL1,BRL3
XI	a	28	5.15-8.03	77.44-113.17	701-1026	85.7%	HAESA, XIP1, HAIKU2, RLK7, PXY, BAM1-3, CLV1, MOL1
	b	20	5.33-6.06	96.55-136.72	870-1254	55.0%	GSO1-2, EDA23, ERL1-2, ERECTA
	c	7	5.94-8.68	96.63-127.25	887-1145	100.0%	PEPR1-2
XII	a	23	5.22-8.56	85.98-126.86	783-1158	60.9%	FLS2, EFR
XII	b	19	5.61-8.44	53.24-115.95	489-1067	52.6%	*Populus* -specific
XIII		34	5.00-9.14	62.81-135.28	565-1605	47.1%	MEE62, TOAD1-2
XIV		10	5.42-8.95	63.75-134.48	574-1237	30.0%	EMS1

Sequence characteristics of each PtLRR-RLK gene subfamily and its phylogenetic relationship with Arabidopsis LRR-RLKs with known functions are shown. Six PtLRR-RLK proteins did not fit well into clusters. Subgroups that do not include any Arabidopsis LRR-RLK proteins are described as Populus-specific. Information on the AGI code, gene full-name and abbreviation for each AtLRR-RLK gene with defined functions is presented in the Additional file 18.

ISSN: 1471-2164