sigma factor

noun

sig·​ma factor ˈsig-mə- How to pronounce sigma factor (audio)
: a detachable polypeptide subunit of RNA polymerase that facilitates the initiation of transcription by recognizing specific DNA promoter sites

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sigma factor
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“Sigma factor.” Merriam-Webster.com Medical Dictionary, Merriam-Webster, https://www.merriam-webster.com/medical/sigma%20factor. Accessed 31 Oct. 2025.

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