Our analysis using data from a model stromal cell line and primary hematopoietic cell populations representing different lineages and developmental stages, suggests that even though several communication pathways are shared, we were able to identify potential stage and lineage restricted pathways that may be involved in events such as lineage restriction.
According to Gould [ 57] (also [ 58] and [ 59]), Wilhelm Haacke devised the word "orthogenesis" which means "straight (line) generation" and subsequently "orthogenesis denotes the claim that evolution proceeds along defined and restricted pathways" [ 57].
Under the constraint argumentation, courtship characters, as long as they invoke also morphological adaptation, might thus evolve rather slowly, and moreover follow restricted pathways, with some characters only being lost and never reacquired during the evolutionary history of a group.
The choice of this lipopeptide anchor is highly important for the immune response, since it allows the targeting, via poorly understood mechanisms (Uhl et al, 1991; Andrieu et al, 2003), of exogenous antigens into MHC class I and class II restricted pathways.
In any event the Ku-dependent telomerase recruitment pathway contributes in part to efficient telomerase binding in S phase, because eliminating the Cdc13-dependent S phase-restricted pathway reduces telomerase binding by only about half, and complete elimination of binding requires inactivation of both pathways (Chan et al, 2008).
For the present study, we were restricted to pathway perturbation experiments using pharmacological inhibitors and recombinant proteins.
In an effort to further enrich for mutations with a functional effect in the tumor, we additionally restricted our pathway analyses to genes expressed in endometrial or colorectal normal tissue.
To overcome this problem, various methods have been developed to target an exogenous Ag into the endogenous MHC class I-restricted pathway.
The selection was restricted to pathways with 4 or more genes represented, resulting in identification of 72 KEGG pathways.
