R&B, soul and funk guitar architect and Bo-Keys member Charles "Skip" Pitts-whose signature riffs are forever immortalized in the Isley Brothers' "It's Your Thing" and the wah-wah on Isaac Hayes' "Theme From Shaft"-died yesterday (May 1) in Memphis. He was 65 and had suffered from lung cancer.

Pitts' pioneering skill with the wah-wah pedal is one of the focal points in the 2011 documentary "Cry Baby: the Pedal That Rocks the World," alongside Buddy Guy, Slash and Eddie Van Halen. In addition to his collaborations with the Isleys and Hayes, Pitts performed and recorded with several other R&B and blues legends, including Sam & Dave, Wilson Pickett, Rufus Thomas and Albert King. He first learned to play guitar in his native Washington, D.C., getting tips from neighbor Bo Diddley. Pitts' first recording was as a 15-year-old on the Gene Chandler hit single "Rainbow 65."

The former Stax Records session player's more recent credits include performing with the Bo-Keys on the score for the film "Hustle and Flow" and Cyndi Lauper's 2010 album Memphis Blues. Featured prominently on the Bo-Keys' 2011 release Got to Get Back!, Pitts also appeared in such films as "Wattstax" and with the Bo-Keys in "Soul Men" starring Bernie Mac and Samuel L. Jackson. Pitts' guitar riffs were sampled by a host of hip-hop artists from Dr. Dre and the Beastie Boys to Eazy-E.

Pitts, who died at Memphis's Methodist Hospital, is survived by his wife Beverly. Burial services are being planned in Washington, D.C.