The control of amount and activity of nuclear proteins is fundamental in regulating gene expression but is unstudied comprehensively in the adaptive response to pathogens. Highly specific labeling, enrichment and measurement of the nuclear proteome using TurboID LC-MS of Arabidopsis thaliana leaves treated with flg22 and/or cycloheximide was done. This discriminated translation followed by protein import, trafficking of preexisting protein, alleviation of repression and protein turn-over in the nucleus upon elicitation of basal immunity. Around 2,000 nuclear proteins were repeatedly quantified including more than 300 transcription factors or proteins related to transcription. Several proteins with documented activity in the endosome and MVBs were synthesized and imported upon PAMP challenge, suggesting alternative nuclear functions in PTI, mainly of an obscure cysteine/histidine rich protein family. Circadian clock components, particularly the transcription factor CHE were depleted upon PAMP challenge, suggesting a safeguard against untimely induction of SAR. Moonlighting proteins exercising alternative functions in the nucleus as well as protein trafficking and turn-over regulation are common in modulating the multi-facetted layers of plant immunity. The highly specific, deep coverage of proteins in the nucleus makes the study a resource for anyone interested in plant nuclear proteome dynamics and defense.