Table I. HUP genes analyzed for function in low-oxygen survival.

Gene Name	Arabidopsis Genome Initiative Locus	Ortholog(s) in Plants	Family Membersa	Molecular Mass	Coexpressed Genesb
				kD
HUP6	At3g27220	Rice, poplar	1_1_1	48.5	Anaerobic metabolism
HUP9	At5g10040	None	2_1_1	9.8	Anaerobic metabolism
HUP17	At1g05575	None	2_2_1	9.5	ERFs, WRKYs
HUP23	At2g36220	Poplarc	2_2_1	29.0	PP2C, ERF4
HUP26	At3g10020	Rice, poplarc	1_1_1	16.7	HSPs, SnRK2, T6PS
HUP29	At5g15120	Rice, poplar	5_2_1	33.0	Anaerobic metabolism
HUP32	At1g33055	Rice, poplar	1_1_1	7.5	Anaerobic metabolism, ETR2, ZF
HUP36	At1g19530	Poplar	1_1_1	13.7	Anaerobic metabolism
HUP37	At2g41730	Poplarc	2_2_2	13.3	ACS2, NAC, ROS response
HUP40	At4g24110	Rice, poplarc	1_1_1	28.6	Anaerobic metabolism
HUP41	At4g33980	Poplarc	1_1_1	24.6	PDC2, ABF1, APRR5, ZF
HUP42	At4g39675	None	1_1_1	8.2	Anaerobic metabolism
HUP43	At5g39890	Rice, poplar	19_7_1	30.8	Anaerobic metabolism
HUP44	At5g66985	None	1_1_1	9.4	Anaerobic metabolism
HUP53	At3g27770	Ricec, poplarc	8_1_1	36.7	Anaerobic metabolism, KCO1
HUP54	At4g27450	Rice, poplar	5_2_2	27.6	Anaerobic metabolism

^aNumber of Arabidopsis genes with 35% or greater, 50% or greater, or 70% or greater amino acid sequence identity from Horan et al. (2008).

^bCoexpression network based on data of Ma et al. (2007) and Horan et al. (2008). Anaerobic metabolism coexpressed genes include one or more of the following: ADH1, PDC1, SUS1, SUS4, and HB1. ABF1, Abscisic acid-responsive element-binding factor 1; ACS2, 1-aminocyclopropane-1-carboxylate synthase 2; APRR5, pseudoresponse regulator 5; ERF, ethylene responsive factor; ETR2, ethylene triple response 2; HSPs, heat shock proteins; KCO1, potassium channel 1; NAC, NAC domain TF family; PP2C, protein phosphatase 2C; SnRK2, SNF1-related protein kinase 2; T6PS, trehalose-6-phosphate synthase; WRKY, WRKY TF family; ZF, zinc finger protein.

^cPutative ortholog(s) identified but not induced by low oxygen (Supplemental Table S9e).