| No. | Description | Name | Size (AA) | Members |
| NUC001 | central domain in Nop56/SIK1-like proteins | NOSIC | 53 | 49 |
| NUC002 | characteristic domain in GAR1-like snoRNPs | GAR1L | 61 | 20 |
| NUC003 | Treacher Collins-Franceschetti syndrome 1 protein tandem repeat | TCOFD | 65 | 3 |
| NUC004 | characteristic repeat of p68-like RNA helicases | P68HR | 35 | 7 |
| NUC006 | characteristic repeat of proliferating cell nuclear antigen P120 | P120R | 23 | 3 |
| NUC007 | KI67/Chmadrin-repeat | KI67R | 113 | 3 |
| NUC008 | novel domain in poly(ADP-ribose)-synthetases; located between zf-PARP domains and BRCT repeats | PADR1 | 57 | 16 |
| NUC009 | novel domain in poly(ADP-ribose) polymerases; associated with zf-PARP, BRCT, SAM, PARP and ankyrin repeats/domains | PADR2 | 76 | 35 |
| NUC010 | characteristic domain in UVSB PI-3 kinase, MEI-41 and ESR1; associated with FAT, FATC, PI3_PI4_kinase modules | UME | 110 | 11 |
| NUC011 | TruB_N/PUA domain associated N-terminal domain of Dyskerin-like proteins | DKCLD | 59 | 27 |
| NUC014 | N-terminal domain in RNP K-like proteins with KH-domains | ROKNT | 45 | 4 |
| NUC016 | N-terminal domain in 3'-5'-exonucleases with HRDC domain; putative exosome components; Polymyositis autoantigen 2 | PMC2NT | 98 | 7 |
| NUC017 | N-terminal domain of ribosomal L6 proteins | RL6NT | 57 | 8 |
| NUC018 | N-terminal domain of ribosomal L30 proteins | RL30NT | 71 | 21 |
| NUC020 | N-terminal domain of ribosomal S11/S17 proteins | RS11NT | 39 | 44 |
| NUC021 | N-terminal domain of ribosomal S13/S15 proteins | RS13NT | 60 | 37 |
| NUC023 | N-terminal domain of Ribosomal S4 / S4e proteins; associated with KOW domains | RS4NT | 41 | 45 |
| NUC029 | C-terminal domain of DNA gyrases B / topoisomerase IV / HATPase proteins | DTHCT | 110 | 15 |
| NUC031 | C-terminal domain in Bloom's syndrome DEAD helicase subfamily | BDHCT | 41 | 4 |
| NUC034 | N-terminal domain in PHD/RING finger and chromo domain-associated helicases | CHDNT | 55 | 7 |
| NUC036 | C-terminal domain A in PHD/RING finger and chromo domain-associated CHD-like helicases | CHDCT1 | 120 | 14 |
| NUC038 | C-terminal domain B in PHD/RING finger and chromo domain-associated CHD-like helicases | CHDCT2 | 180 | 11 |
| NUC045 | N-terminal domain in family of CCR4-associated factor-like proteins with zf-CCCH and R3H domains; part of the CCR4/NOT transcription complex | CAFNT | 136 | 34 |
| NUC046 | C-terminal domain in Poly(A)-specific ribonucleases | PARNUCT | 46 | 9 |
| NUC056 | domain in ILF3/p122/NF45 transcription factors; associated with dsrm repeats | IPN | 154 | 43 |
| NUC059 | C-terminal domain of NONA and PSP1 proteins | NOPS | 53 | 20 |
| NUC060 | SMC hinge region | SMChinge | 153 | 86 |
| NUC062 | characteristic domain of CCAAT-box binding transcription factors and MAK21-like proteins; implications in ribosome biogenesis and transcription regulation | CBFMK21 | 40 | 19 |
| NUC063 | novel putative zinc-binding domain (CHHC motif) in RNP H and F; rrm repeat-associated | zf-RNPHF | 36 | 6 |
| NUC064 | C-terminal repeat in RBM1-like RNA binding hnRNPs; associated with rrm repeats in the N-terminus | RBM1CTR | 46 | 15 |
| NUC068 | central domain in Poly(rC)-binding proteins; associated with KH domain | PrCBPCN | 132 | 14 |
| NUC069 | N-terminal domain in pre-mRNA splicing factors of PRO8 family | PRO8NT | 155 | 13 |
| NUC071 | central domain in pre-mRNA splicing factors of PRO8 family | PROCN | 426 | 13 |
| NUC072 | C-terminal domain in pre-mRNA splicing factors of PRO8 family | PRO8CT | 129 | 13 |
| NUC083 | novel domain C-terminal to WD40 repeats in Dom34p-interacting protein 2 from yeast; role in regulation of translation | DIP2CT | 103 | 8 |
| NUC086 | conserved region in proteins of the Bystin family; interaction with trophinin, tastin and cytokeratin; unusual occurence in nucleolar protein | BysCR | 256 | 9 |
| NUC087 | C-terminal domain characteristic of NOG subfamily of nucleolar GTP-binding proteins | NOGCT | 134 | 15 |
| NUC091 | N-terminal domain characteristic for subfamily of hypothetical nucleolar GTP-binding proteins similar to human NGP1 | NGP1NT | 134 | 14 |
| NUC094 | present in proteins of the Ferlin family; often central between two C2 domains | FerI | 72 | 10 |
| NUC095 | central domain A in proteins of the Ferlin family | FerA | 67 | 18 |
| NUC096 | central domain B in proteins of the Ferlin family | FerB | 79 | 18 |
| NUC098 | central domain C in proteins of the Ferlin family | FerC | 120 | 18 |
| NUC102 | C-terminal conserved domain of traube proteins | TRAUB | 87 | 11 |
| NUC103 | central domain hypothetical nucleolar proteins of novel family defined by alignments NUC103/104 | NUC103/4 | 156 | 8 |
| NUC104 | C-terminal domain hypothetical nucleolar proteins of novel family defined by alignments NUC103/104 | NUC103/4 | 149 | 8 |
| NUC105 | N-terminal domain of maleless-like RNA helicase family | MLENT | 128 | 6 |
| NUC108 | C-terminal domain of maleless-like RNA helicase family | MLECT | 41 | 45 |
| NUC109 | central domain of proteins from DNA polymerase type V subfamily | DPOCT | 71 | 7 |
| NUC110 | central domain between Ubox (RING-finger like) domain and WD40 repeats in spliceosome/cdc5p-associated proteins; possibly degenerated WD40 repeats | CDC5PAD | 117 | 10 |
| NUC111 | N-terminal domain in pescadillo-like proteins with BRCA1 C-terminus domain | PESCNT | 139 | 10 |
| NUC114 | N-terminal domain in UBF transcription factors; possibly degenerated HMG box | NUBF | 100 | 9 |
| NUC119 | C-terminal domain in Penguin-like proteins associated with Pumilio repeats | CPL | 159 | 3 |
| NUC121 | AARP2 central domain; weakly similar to GTP-binding domain of elongation factor TU | AARP2CN | 91 | 18 |
| NUC123 | AARP2 family C-terminal domain | AARP2CT | 208 | 19 |
| NUC125 | central conserved domain in novel family of hypothetical proteins defined by NUC125 | NUC125 | 73 | 9 |
| NUC126 | novel family of hypothetical nucleolar proteins defined by NUC126 | NUC126 | 194 | 12 |
| NUC127 | N-terminal domain in RNA-binding proteins of the NOP5 family | NOP5NT | 68 | 27 |
| NUC129 | C-terminal domain in novel family of hypothetical nucleolar proteins defined by NUC129 | NUC129 | 63 | 4 |
| NUC130 | N-terminal domain of novel nucleolar protein family defined by NUC130/133; weakly similar to TFIIF beta subunit | NUC130/3NT | 52 | 8 |
| NUC133 | C-terminal domain of novel family of nucleolar proteins defined by NUC130/133 | NUC130/3CT | 114 | 11 |
| NUC135 | redefined Nle domain of a family of proteins founded by fly notchless protein and yeast microtubule-associated protein YTM1; located N-terminal to WD40 repeats | NLE | 71 | 13 |
| NUC136 | novel C2HC-type zinc finger in LYAR-like cell growth-regulating proteins; associated with rrm domains; present in one or two copies per protein | zf-LYAR | 62 | 8 |
| NUC141 | C-terminal domain in BING4 family of nucleolar WD40 repeat proteins | BING4CT | 80 | 12 |
| NUC142 | characteristic KR-rich domain for novel family of nucleolar proteins; SAS10 is a derepressor of silencing; LCP5 is a U3 snRNP component; domain is combined with a basic leucine zipper in one protein | KRSL | 69 | 12 |
| NUC145 | central domain in NNP1/RRP1-like proteins | NNRR | 144 | 10 |
| NUC152 | C-terminal domain characteristic for RNA helicase II / Gu protein family | GUCT | 108 | 14 |
| NUC153 | small domain in novel nucleolar protein family defined by NUC153 | NUC153 | 30 | 8 |
| NUC156 | C-terminal domain in nucleolar proteins of family NUC156 | NUC156 | 151 | 6 |
| NUC160 | characteristic C-terminal domain for Dbp10p subfamily of hypothetical RNA helicases | DBP10CT | 68 | 8 |
| NUC161 | N-terminal domain of CARG-binding factor A-like proteins; combined with rrm domains | CBFNT | 76 | 12 |
| NUC162 | characteristic domain N-terminal to ARID/BRIGHT domain in DNA binding proteins of Retinoblastoma-binding protein 1 family | RBB1NT | 100 | 4 |
| NUC164 | N-terminal domain in MAK16-like proteins | MAK16NT | 139 | 12 |
| NUC167 | central domain in nucleolar proteins of family NUC167 | Y112CN | 50 | 10 |
| NUC168 | central domain in nucleolar proteins of the multicopy repressor of ras (Mra) family | MRACN | 79 | 16 |
| NUC169 | N-terminal domain in BOP1-like WD40 proteins | BOP1NT | 286 | 9 |
| NUC173 | central domain of novel family of hypothetical nucleolar proteins defined by NUC173 | NUC173 | 203 | 8 |
| NUC176 | C-terminal domain in Nopp140-like proteins | NOPP140CT | 72 | 9 |
| NUC177 | N-terminal domain defining a novel family of nucleolar translational activator proteins with HEAT repeats | TAHNT | 66 | 5 |
| NUC185 | characteristic C-terminal domain of DOB1/SKI2/helY-like DEAD box helicases | DSHCT | 202 | 24 |
| NUC188 | novel domain in family POP1-like nucleolar proteins | POPLD | 108 | 6 |
| NUC189 | characteristic domain in NUC189 family of nucleolar proteins | NUC189 | 90 | 9 |
| NUC191 | domain A in the catalytic subunit of DNA-dependent protein kinases | NUC191 | 515 | 4 |
| NUC194 | domain B in the catalytic subunit of DNA-dependent protein kinases | NUC194 | 399 | 4 |
| NUC200 | characteristic domain in U3 snRNP mpp10-like proteins | MPP10 | 88 | 7 |
| NUC201 | N-terminal domain in hypothetical nucleolar proteins with NUC202 tandem repeat | NUC201 | 86 | 4 |
| NUC202 | NUC202 repeat; characteristic for a novel family of nucleolar proteins | NUC202 | 76 | 4 |
| NUC203 | C-terminal domain in novel family of hypothetical nucleolar WD40 repeat proteins | NUC203 | 87 | 5 |
| NUC205 | characteristic domain for novel family NUC205 of nucleolar proteins | NUC205 | 44 | 3 |
| NUC209 | N-terminal domain of BAP28-like nucleolar proteins | BP28NT | 286 | 6 |
| NUC211 | C-terminal domain of BAP28-like nucleolar proteins | BP28CT | 171 | 6 |
| NUC213 | N-terminal domain in hypothetical nucleolar proteins of novel NUC213 family | NUC213 | 36 | 14 |