U4

U-4, U04 or U4 may refer to:

• U4 spliceosomal RNA, a non-coding RNA component of the major U2-dependent spliceosome
• Anti-Corruption Resource Centre, based at the Chr. Michelsen Institute in Bergen, Norway
• Haplogroup U4 (mtDNA), a human genetic group
• U4, an unemployment figure released by the United States Bureau of Labor Statistics
• U04, Severe acute respiratory syndrome ICD-10 code
• U4, unitary group of degree 4
• Ultima IV: Quest of the Avatar, a video game
• U-47700, a synthetic opioid

Transport

• Underground railways
  • U4 (Berlin U-Bahn), a subway line in Berlin, Germany
  • U4 (Frankfurt U-Bahn), a subway line in Frankfurt, Germany
  • U4, a Hamburg U-Bahn line
  • U4, a Munich U-Bahn line
  • U4, a Vienna U-Bahn line.
• German submarine U-4, one of several German submarines
• London Buses route U4
• U-4, the U.S. Air Force version of the Aero Commander (aircraft), a light twin-engined aircraft from Aero Design and Engineering Company
• U-4, the Japanese air self-defense force designation for the Gulfstream IV aircraft
• U4, PMTair (former) IATA airline designator
• U4, Buddha Air current IATA airline designator

See also

• 4U (disambiguation)