Encapsidates the genome protecting it from nucleases (Probable). The encapsidated genomic RNA is termed the nucleocapsid (NC) and serves as template for transcription and replication (Probable). The nucleocapsid has a left-handed helical structure (By similarity). As a trimer, specifically binds and acts as a chaperone to unwind the panhandle structure formed by the viral RNA (vRNA) termini (PubMed:15650206, PubMed:15254200, PubMed:21378500, PubMed:16971445, PubMed:25062117, PubMed:16775315). Involved in the transcription and replication initiation of vRNA by mediating primer annealing (PubMed:20164193). Plays a role in cap snatching by sequestering capped RNAs in P bodies for use by the viral RdRp during transcription initiation (PubMed:19047634). Substitutes for the cellular cap-binding complex (eIF4F) to preferentially facilitate the translation of capped mRNAs (PubMed:18971945, PubMed:25062117). Initiates the translation by specifically binding to the cap and 40S ribosomal subunit (PubMed:20844026, PubMed:20164193, PubMed:25062117). Prevents the viral glycoprotein N (Gn) from autophagy-dependent breakdown maybe by blocking autophagosome formation (By similarity). Inhibits host EIF2AK2/PKR dimerization to prevent PKR-induced translational shutdown in cells and thus the activation of the antiviral state (By similarity). Also displays sequence-unspecific DNA endonuclease activity (PubMed:27261891). Homotrimer (PubMed:15650206, PubMed:15254200, PubMed:25062117). Homomultimer (PubMed:26559827). Homomultimerizes and binds to viral genomic RNA to form the nucleocapsid (By similarity) (PubMed:26559827). Interacts with host MAP1LC3B; this interaction participates to the protection of Gn from virus-triggered autophagy. Interacts with host SNAP29; this interaction participates to the protection of glycoprotein N from virus-triggered autophagy (By similarity). Interacts (via N-terminus) with host RPS19; this interaction probably mediates the loading of the 40S ribosomal subunit on viral capped mRNA during N-mediated translation initiation (PubMed:20844026, PubMed:25062117). Interacts with the viral RdRp; this interaction is required for RdRp function (PubMed:24850733). Interacts with host SUMO1 (via N-terminus) (By similarity). Interacts with host DAXX (By similarity). Interacts with the viral glycoprotein N (via C-terminus) (By similarity). Interacts with the viral glycoprotein C (via C-terminus) (By similarity). Internal protein of virus particle. The N-terminus is required for chaperone activity and, in trimeric form, this region likely serves in high affinity vRNA panhandle recognition (PubMed:21378500). The N-terminus also contains a coiled coil region, which probably participates in but is insufficient to initiate N trimerization (PubMed:17222867). The YxxL motif is indispensable for the interaction with host MAP1LC3B (By similarity). The central region is involved in specific RNA-binding (By similarity). Has distinct cap- and RNA-binding sites so it can bind simultaneously both the vRNA and mRNA cap (PubMed:20164193). Belongs to the hantavirus nucleocapsid protein family.