Meanwhile, HBx mutants with distal 14 amino acids or 35 amino acids deletion were discovered in the present study as well as in previous investigation (Yip et al, 2011), suggesting that these two mutants may exist universally.
Thus, electrolyte leakage data in nec1 were generally in agreement with the expected "defense, no death" phenotype characteristic of hlm1/ dnd2 mutants, although differences between nec1 and hlm1/ dnd2 mutants may exist in this respect.
Likewise, variation may exist between different institutions.
This possibility highlights an outstanding unresolved issue in experimental evolution, namely the extent to which adaptation results from accumulation of de novo mutations as opposed to selection of rare adaptive mutants that may exist at the onset of selection.
A universal dnaQ mutant that can effectively improve all physiological traits might not exist, while a group of dnaQ mutants may be helpful, as the most preferable dnaQ mutants will be enriched during the evolution process.
These numbers are much higher than the number of possible mutant strains that can be generated, indicating that all the single and double mutant resistant viruses may exist before treatment and rapidly compete with the wildtype virus during therapy.
However, at 22 DAA, GPC-A2 expression was significantly lower in WT plants than in either gpc-A1 (P = 0.024) or gpc-A1/gpc-B2 (P = 0.004) mutants, suggesting that there may exist some GPC-mediated feedback mechanism on the regulation of GPC-A2 transcript levels (Additional file 1: Figure S5).
Nevertheless, the levels of other DILP genes, especially DILP1, were elevated in DILP6 mutant animals, suggesting that compensatory mechanisms may exist that may reduce the severity of DILP6 loss of function.
However, additional miRNA export mechanisms may exist in plants as hasty mutants showed a decreased accumulation of some, but not all miRNAs [ 25].
Furthermore, interactions between HARP and DNA-PK may exist that are not strong enough for the mutant HARP to co-purify with DNA-PK, but are strong enough for HARP to affect the ability of DNA-PK to phosphorylate RPA.
It should be noted, however, that each of these studies employed double mutant mice, and are thus not necessarily reflective of the condition which may exist in the absence of Cry2 only.
