Several germ line genes become ectopically expressed in somatic tissues of long-lived C. elegans mutants. Somatically-expresssed germ line factors appear to serve a crucial function, as knocking down any of these genes drastically reduces longevity only in the long-lived mutants (Ewen-Campen et al., 2010).

RNAi against the germ line-restricted genes abrogated longevity conferred by daf-2 mutation, while in wild-type it resulted in increased longevity. A rational explanation is that in wild-type, germ-line restricted genes are only present in the germ line. Their knockdown has no effect on somatic tissue, but might reduce the activity of the germ line cells. Ablating the gonad has life-span extending consequences in wild-type. Such factors may operate as an interacting module, capable of being induced by a variety of upstream signals. Downstream targets of germ line factors have evolved in lineage-specific ways (Ewen-Campen et al., 2010). In CeMM is dramatically increased in expression, which is upregulated in lin-35; slr-2 double mutant. Knockdown or overexpression of DR-essential aak-2/AMPK (Curtis et al., 2006) decrease or increase lifespan by around 14% respectively.

Sexing up the soma: http://ouroboros.wordpress.com/2009/06/16/2638/ Not-so-disposable Somas: http://www.anti-agingfirewalls.com/2011/10/03/not-so-disposable-somas-proof-of-concept-studies-for-increasing-lifespan/