Lifespan extension and increased pumping rate accompany pharyngeal muscle‐specific expression of nfi ‐ 1 in C. elegans

Caenorhabditis elegans nfi ‐ 1 belongs to the Nuclear Factor I (NFI) family of transcription factors known to regulate metazoan gene expression and development. We showed previously that loss of nfi ‐ 1 in worms results in multiple behavioral defects; slower pharyngeal pumping rate, impaired egg laying, defective motility, and a shortened life span. Here, we generated cell‐type specific transgenic worms to determine the cells in which nfi ‐ 1 must be expressed to rescue the pharyngeal pumping defect. Expression of nfi ‐ 1 from the pharyngeal muscle‐specific myo ‐ 2 promoter, but not from the F25B3.3 or myo ‐ 3 promoters, rescued the pharyngeal pumping defect of nfi ‐ 1 worms. Surprisingly, myo ‐ 2 ‐driven nfi ‐ 1 expression also rescued the shortened lifespan of nfi ‐ 1 worms, demonstrating a possible cell‐autonomous role of nfi ‐ 1 in pharyngeal muscle for both phenotypes. We propose some relationships between the pharyngeal pumping and lifespan phenotypes and potential mechanisms of nfi ‐ 1 function. Developmental Dynamics 237:2100–2107, 2008. © 2008 Wiley‐Liss, Inc.