He wrote “Mull of Kintyre” with Paul McCartney and was inducted into the Rock & Roll Hall of Fame with the Moody Blues.Denny Laine, a singer, songwriter and guitarist who co-founded two of the biggest British rock bands of the 1960s and ’70s, the Moody Blues and Wings, before embarking on a long solo career, died in Naples, Fla., on Tuesday — 50 years to the day after Wings released its most successful album, “Band on the Run,” in the U.S. He was 79.His wife, Elizabeth Mele-Hines, said the cause of death, at a hospital, was interstitial lung disease.Mr. Laine was part of the efflorescence of British rock music in the early 1960s, when many young musicians were still soaking up the influence of American blues. Performers like Eric Clapton, Spencer Davis and the Beatles became not just friends with Mr. Laine but also frequent collaborators with him.A native of Birmingham, England, he moved to London after his first band, Denny Laine and the Diplomats, broke up. In 1964, he joined four other Birmingham-area transplants, Graeme Edge, Mike Pinder, Ray Thomas and Clint Warwick, to form the M&B 5, a rhythm-and-blues band named after a Birmingham brewery. They soon changed their name to the Moody Blues.Mr. Laine was with the band for only two albums, but in 1964 he sang lead on its first No. 1 hit, “Go Now!” The success of that song, a cover of an R&B song recorded that same year by Bessie Banks, won the Moody Blues slots on a series of high-profile tours, opening for acts like Chuck Berry and the Beatles.Mr. Laine, right, with his fellow members of the Moody Blues in an undated photo. From left were Ray Thomas, Clint Warwick, Graeme Edge and Mike Pinder.Hulton Archive/Getty ImagesMr. Laine left the Moody Blues in 1966 over artistic differences and spent the next five years working on solo projects and with, among other bands, the short-lived jazz-rock ensemble Ginger Baker’s Air Force. It was while singing and playing guitar with that band that he caught the attention of Paul McCartney.By 1971, Mr. McCartney was more than a year out of the Beatles and looking to form a new band. One day, from his rural home west of Glasgow, he cold-called Mr. Laine.“He said, ‘Do you want to do something? Get on a plane, we’re in Scotland,’” Mr. Laine recalled in an interview with The Boston Globe in 2019. The two added Mr. McCartney’s wife, Linda McCartney, and the three — with a rotating cast of other bandmates — became Wings.Though Wings is often remembered as a McCartney vehicle — at times it went by the name Paul McCartney and Wings — Mr. Laine was an equal member.He appeared on all seven of the group’s studio albums, sang lead and played lead guitar on several prominent tracks and wrote or co-wrote a number of the band’s songs, including “Mull of Kintyre,” which reached No. 1 on the British charts and sold more than two million copies. (He also claimed to have had a hand in writing another No. 1 Wings hit, “Band on the Run,” although Paul and Linda McCartney are the only credited writers.)Mr. Laine received four Grammy nominations with Wings and won two: best pop vocal performance by a duo, group or chorus in 1975, for “Band on the Run,” and best rock instrumental performance in 1980, for “Rockestra Theme.”“Me and him had this kind of feel together musically,” Mr. Laine said about working with Mr. McCartney in an interview with Guitar World this year. “We slotted in well together. We could read each other, and that came from growing up on the same musical influences. Paul’s got a good sense of rhythm, and he doesn’t overplay, which I like.”Mr. Laine was inducted into the Rock & Roll Hall of Fame in 2018 as a founding member of the Moody Blues. In what many critics and fans consider one of the bigger snubs in the Hall of Fame’s history, Wings has yet to follow.Mr. Laine in 1972, a year after Paul McCartney cold-called him asking him to join a new band, Wings.Michael Putland/Getty ImagesBrian Frederick Hines was born on Oct. 29, 1944, in Birmingham. His parents, Herbert and Eva (Basset) Hines, worked in factories.Denny was a childhood nickname, and he later added the surname Laine as a nod to one of his sister’s favorite singers, Frankie Laine.He grew up listening to the so-called Gypsy jazz of musicians like Django Reinhardt and Stéphane Grappelli, as well as to Spanish guitar — a love he explored in between his time with the Moody Blues and Wings, when he lived in Spain and studied flamenco.After returning to Britain, he formed two bands, the Electric String Band and Balls, both of which fizzled — though the first, which featured a string section and lush orchestration, would greatly influence a similarly named band, the Electric Light Orchestra.He counted the McCartneys among his closest friends, but he left Wings in 1981 after Mr. McCartney was arrested in Japan for marijuana possession. Mr. Laine’s departure ended the band and put a strain on their relationship, though he later played on several of Mr. McCartney’s solo projects.Mr. Laine performing this March at the City Winery in Manhattan. He continued to record and tour regularly in the four decades after Wings split up.Al Pereira/Michael Ochs Archives, via Getty ImagesMr. Laine married Joanne Patrie in 1978; they divorced in 1981. He married Rosha Kasravi in 2003; they later separated and divorced in 2021. He married Elizabeth Mele this year. Along with her, his survivors include two children from his first marriage, Heidi and Laine Hines; three other children, Damian James, Ainsley Adams and Lucy Grant; his sister, Doreen; and several grandchildren.Even while he was with Wings, Mr. Laine kept up a spirited solo career, releasing two albums in the 1970s: “Ahh … Laine” (1973) and “Holly Days” (1977), a tribute to Buddy Holly.He continued to work and tour regularly in the four decades after the band split up, playing a mix of his own compositions and material from the Moody Blues and Wings. Often he would perform what he called “Songs and Stories,” a combination of music and tales from his rock life.“I can’t live without live work,” he told Guitar World. “There’s no substitute for playing live and getting the feeling of connecting with an audience.” More