Downregulated expression of HSP27 in human low-grade glioma tissues discovered by a quantitative proteomic analysis

Table 1 The expression quantification of β-actin and HSPs by the unique Leu-containing isotope peptides in MS

		MOWSE scores(b) (Queries Match)		SILAC-Ratio(e) (mean ± SD; No. of Pep ^f )		Unique Leu-containing peptide coverage(%)
Protein name	IPI no.(a)	HGTs (c)	PBTs (d)	Ratio1	Ratio2	HGTs (c)	PBTs (d)	Change-Ratio(g) (ratio1/ratio2)
HSP110/100 family
HSP H1(105 KD)	IPI00218993	77(8)	140(10)	0.61 ± 0.02 (2)	0.82 ± 0 (1)	2.7	1.6	0.74
HSP90 family
HSP90 AB1	IPI00334775	428(18)	179(10)	0.29 ± 0.17 (6)	0.45 ± 0.26 (3)	8.7	4.8	0.64
HSP90 AA1	IPI00382470	82(14)	109(11)	0.80 ± 0.43 (4)	0.75 ± 0.52 (2)	6	3	1.07
HSP70 family
HSP A8(71 KD)	IPI00003865	486(16)	360(17)	0.52 ± 0.09 (8)	0.55 ± 0.1(3)	17	5	0.95
HSP A9(70 KD)	IPI00007765	401(16)	127(5)	0.49 ± 0.09 (5)	0.34 ± 0 (1)	9.6	2.2	1.44
HSP A5(70 KD)	IPI00003362	508 (15)	99(8)	0.33 ± 0.15 (7)	0.57 ± 0.28 (2)	14	3.2	0.58
HSP60 family
HSP D1(60 KD)	IPI00472102	67(9)	419(20)	0.57 ± 0.08 (3)	0.52 ± 0.27(4)	33	18	1.10
Small HSP family
HSP B1(27 KD)	IPI00025512	159(12)	138 (10)	0.29 ± 0.12 (4)	0.61 ± 0.32 (3)	8.2	7	0.48
Control protein
β-actin	IPI00021439	687(31)	643(39)	1.03 ± 0.02 (4)	0.98 ± 0.03 (4)	12	12	1.05

(a) IPI (International Protein Index) no. is the protein accession number, which was derived from the EMBL-EBI database.
(b) 'MOWSE' is derived from molecular weight search, and it is a method for the identification of proteins from the molecular masses of peptides created by proteolytic digestion and measured by MS.
(c) The protein mixture from HGTs and Leu-d₃labeling H4 cells; HGTs: human glioma tissues.
(d) The protein mixture from PBTs and Leu-d₃labeling H4 cells; PBTs: para-cancerous brain tissues.
(e) SILAC ratio1 (HGTs/H4) and SILAC ratio2 (PBTs/H4): the peak intensity ratio of Leu-d₀-labeling peptides from HGTs or PBTs versus that of Leu-d₃-labeling peptides from H4 cells, which was quantified using Analyst QS software.
(f) The number of unique Leu-containing peptides of one protein to calculate SILAC ratio1 and SILAC ratio2.
(g) The Change-Ratio between two tissues (SILAC Ratio1/SILAC Ratio2).

ISSN: 1477-5956