Some characteristics of the 12 LEAP classes.

aMeaning of the regular expression syntax used for motifs: «.» = any amino acid; X{n, } = at least n times X; X{n,m} = n to m times X; [XY] = X or Y; [∧XY] = neither X nor Y; (XY) = X followed by Y; X? = X present or not; XY$ = XY at the end; (M1)|(M2) = motif M1 or motif M2 or both.bNumber of sequences in LEAPdb using the motif indicated.cAmino acid sequences length range of LEAP classes in LEAPdb.dConsensus sequences of the LEAP classes obtained using Multalin [74]: alignment of all sequences of each LEAP class was performed with a low consensus value (CV) = 35% and a high consensus value = 60% (i.e., above the «twilight zone» [31]) with a PAM matrix (since sequences of each LEAPs class are either distant or not). Gap penalties values (gap open penalty = 2/gap extension penalty = 0/no gap penalty for extremities) were chosen in order to have not stringent conditions for the alignments, thus introducing numerous gaps (see the gaps percentage). This «local - global alignment» of each LEAP class sequences leads to a consensus sequence for each LEAP class, revealing a high level of similarity between those sequences (also much above the «twilight zone»), especially in the case of LEAP classes 3, 5, 7, 10, 11 and 12.eMotif class 4: STTAPGHY|HKTGTTTS|GGGGIGTG|HS[DR]N?K$|DVE$|LH(TRASHEES)?$|C?TGH$|DKLPGQH$|QQN(KTGCD)?$| RGD$|KEGY$|GHRPQI$|GHNN$|SFKS$|GTHKGL$|SSRDNY$|GQSK$|HRDV$|NDL$.fMotif class 6: [∧LNP][∧G][ADEGILMQRSTVY] [AEKQRSTY].[KR][AT].[ADENT][∧DP][EGIKLMQST].{1,67}[∧DER][∧AS]K[AD][∧IL][∧N].[∧E]?.{1,6}G?