On a stoichiometric basis, the most abundant peptides are subunit A (63-72 kD), subunit B (52-60 kD) and subunit c (16-20 kD).
As revealed by rotational image analysis  and image averaging techniques , the V-ATPase head contain 3 copies each of the subunit A and B, which are seen as a hexameric structure.
Wan, C.-Y., and Wilkins, T.A., 1999, "Functional complementation of yeast vma1 cells by a plant subunit A homolog rescues the mutant phenotypes and partially restores vacuolar [H.sup.+]-ATPase activity," The Plant J., 17, pp.
 Lehr, A., Kirsch, M., Viereck, R., Schiemann, J., and Rausch, T., 1999, "cDNA and genomic cloning of sugar beet V-type H+-ATPase subunit A and c isoforms: evidence for co-ordinate expression during plant development and co-ordinate induction in response to high salinity," Plant Mol.
First, the "satisfied" executives may have awarded the HR subunit a large budget, implying that effectiveness leads to resources.
Using the human resource (HR) subunit as the focus for assessment, several core postulates of the multiple constituency model of effectiveness were examined empirically.