Table 4.

SCOP Superfamilies Associated With Transmembrane Proteins

SCOP Superfamily Human Fly Worm Yeast
N % R N % R N % R N % R
Immunoglobulin46338 1 12626 4 7416 5
Cadherin44072 2 20693 1 11484 2
Fibronectin type III35943 3 13454 3 6630 7
EGF/laminin21618 4 13943 2 16339 1
Ligand-binding domain of low-density lipoprotein receptor12651 5 10654 5 7955 4
P-loop containing nucleotide triphosphate hydrolases8710 6 8915 6 9118 3 4110 1
Protein kinase-like (PK-like)6512 7 2710 12 7217 6
Complement control module/SCR domain5620 8 2544 13 36 65
C-type lectin-like5336 9 38 54 3411 8
MHC antigen-recognition domain4782 10
TNF receptor-like3873 11 2100 67
RNI-like3435 12 3135 8 1438 23
Serine protease inhibitors3225 13 1741 19 1821 19
Periplasmic binding protein-like I2893 14 1673 22 3088 11
ConA-like lectins/glucanases2720 15 2842 10 2726 12 563 10
RING-finger domain, C3HC42512 16 1716 19 2016 18 515 10
L domain-like2521 16 2526 13 2316 15 18 38
Spermadhesin, CUB domain2419 18 4250 7 2313 15
(Phosphotyrosine protein) phosphatases II2321 19 717 30 1414 23
EF-hand238 19 159 24 108 29
Metalloproteases (“zincins”), catalytic domain2233 21 415 43 816 37
POZ domain2218 21 55 37 2215 17
C2 domain (Calcium/lipid-binding domain, CaLB)2111 23 1725 19 3236 10 1650 2
Ankyrin repeat218 23 1815 18 3427 8 516 10
Extracytoplasmic domain of cation-dependent  mannose 6-phosphate receptor1588 32 1100 38
SpoIIaa583 63 4100 43 5100 53 2100 25
Adenylyl and guanylyl cyclase catalytic domain1667 29 2876 10 2670 13
Blood coagulation inhibitor (disintegrin)1867 26 343 54 467 58
Periplasmic binding protein-like II1662 29 3077 9 1292 25
Syntaxin 1A N-terminal domain862 47 556 37 862 37 788 5
L-2-Haloacid dehalogenase1161 34 210 67 528 53 213 25
Snake toxin-like556 63 2100 67 150 98
Metal-binding domain655 58 480 43 480 58 571 10
Transferrin receptor ectodomain, apical domain754 53 250 79 375 20

[i] The table gives the number (N) of domains in each superfamily that are found in sequences that have a transmembrane section. The “%” is percentage of the toal occurrence of each domain in the proteome (i.e., transmembrane and nontransmembrane chains, see Table 1). R denotes the rank of N. The lower part of the table details superfamilies with highest percentages in membrane proteins and with a frequency of at least five domains in human that are not reported in the upper part.