. Author manuscript; available in PMC: 2010 Nov 1.

Published in final edited form as: Mech Ageing Dev. 2009 Nov–Dec;130(11-12):784–792. doi: 10.1016/j.mad.2009.10.004

Table 2. Mass spectrometry results.

A semi quantitative estimate of the relative abundance of protein from nuclear extracts used for DNA end binding and Western analysis was obtained by comparing total peptide ion current in Mass Spectrometry. The Mass Spectrometry analysis was performed on trypsin digests of two regions of a polyacrylamide gel. One region was from the bottom of the well to 97 kDa and in this region 349 proteins were detected in cow and 381 in human. Another region was from 97 kDa to 65 kDa and in this region 366 proteins were detected in cow and 314 in human. Filamin A and HSP90α are shown here as controls for the capacity of the Mass Spectrometer to detect abundant proteins in both species.

Region of polyacrylamide gel analyzed	Protein Name	COW	HUMAN
		Position in descending list of proteins ordered by Total Ion Current	Position in descending list of proteins ordered by total Ion Current (Total Ion Current)
> 97 kDa	Filamin A	1^st of 349 (7.6e8)	1^st of 381 (2.4e8)
> 97 kDa	DNA-PKcs	No Peptides detected	6^th of 381 (7.6e7)
Between 65 kDa and 97 kDa	HSP90ƒ¿	4^th of 366 (1.5e7)	1^st of 314 (2.7e7)
	Ku 80	274^th of 366 (1.4e5)	3^rd of 314 (2.1e7)
	Ku 70	355^th of 366 (5.3e4)	2^nd of 314 (2.5e7)