ZNHIT6 (zinc finger HIT-type containing 6), also known as BCD1, is an essential assembly factor for box C/D small nucleolar ribonucleoproteins (snoRNPs) involved in ribosome biogenesis. The protein contains a zinc-finger HIT domain (ZHD) with interleaved CCCC and CCHC zinc finger motifs that facilitate protein-protein interactions rather than direct RNA binding 1. ZNHIT6 maintains box C/D snoRNA steady-state levels and ensures their proper accumulation and nucleolar localization, critical steps in pre-ribosomal RNA processing and large ribosomal subunit (LSU-rRNA) maturation 1. The protein functions as a cotranscriptional assembly factor that directs the sequential loading of core snoRNP proteins, particularly Nop58, onto nascent snoRNA transcripts during the biogenesis process 2. ZNHIT6 activity is particularly important under heat stress conditions, where its ZHD maintains functional protein folding 1. Clinically, ZNHIT6 expression alterations associate with emphysema severity in chr1 obstructive pulmonary disease (COPD) patients, suggesting a potential link between impaired snoRNP biogenesis and pulmonary pathology 3. The functional importance of ZNHIT6 in ribosome assembly indicates that dysregulation could impact protein synthesis capacity in affected tissues.