WARNING:
This document is under construction and may contain errors!
Amino Acid Sequence of Human CD11a

Domains are colored as given by Swiss-Prot ( ITAL_HUMAN P20701, also at NCBI Entrez as accession 1170591).
Also indicated is the "I domain" crystallized by Qu & Leahy.
Total length (without signal sequence) is 1145 amino acids.
Signal sequence length 25   Extracellular length 1063
Possible N-linked glycosylation   I domain    MIDAS (see Lee, Bergelson)
Discrepancy R -> W found by Qu & Leahy. 
        1 MKDSCITVMA MALLSGFFFF APASSYNLDV RGARSFSPPR AGRHFGYRVL QVGNGVIVGA
       61 PGEGNSTGSL YQCQSGTGHC LPVTLRGSNY TSKYLGMTLA TDPTDGSILA CDPGLSRTCD
      121 QNTYLSGLCY LFRQNLQGPM LQGRPGFQEC IKGNVDLVFL FDGSMSLQPD EFQKILDFMK
                                         ^ begin Qu/Leahy   
      181 DVMKKLSNTS YQFAAVQFST SYKTEFDFSD YVKRKDPDAL LKHVKHMLLL TNTFGAINYV
      241 ATEVFREELG ARPDATKVLI IITDGEATDS GNIDAAKDII RYIIGIGKHF QTKESQETLH
      301 KFASKPASEF VKILDTFEKL KDLFTELQKK IYVIEGTSKQ DLTSFNMELS SSGISADLSR
                                end Qu/Leahy    ^
      361 GHAVVGAVGA KDWAGGFLDL KADLQDDTFI GNEPLTPEVR AGYLGYTVTW LPSRQKTSLL
      421 ASGAPRYQHM GRVLLFQEPQ GGGHWSQVQT IHGTQIGSYF GGELCGVDVD QDGETELLLI
      481 GAPLFYGEQR GGRVFIYQRR QLGFEEVSEL QGDPGYPLGR FGEAITALTD INGDGLVDVA
      541 VGAPLEEQGA VYIFNGRHGG LSPQPSQRIE GTQVLSGIQW FGRSIHGVKD LEGDGLADVA
      601 VGAESQMIVL SSRPVVDMVT LMSFSPAEIP VHEVECSYST SNKMKEGVNI TICFQIKSLY
      661 PQFQGRLVAN LTYTLQLDGH RTRRRGLFPG GRHELRRNIA VTTSMSCTDF SFHFPVCVQD
      721 LISPINVSLN FSLWEEEGTP RDQRAQGKDI PPILRPSLHS ETWEIPFEKN CGEDKKCEAN
      781 LRVSFSPARS RALRLTAFAS LSVELSLSNL EEDAYWVQLD LHFPPGLSFR KVEMLKPHSQ
      841 IPVSCEELPE ESRLLSRALS CNVSSPIFKA GHSVALQMMF NTLVNSSWGD SVELHANVTC
      901 NNEDSDLLED NSATTIIPIL YPINILIQDQ EDSTLYVSFT PKGPKIHQVK HMYQVRIQPS
      961 IHDHNIPTLE AVVGVPQPPS EGPITHQWSV QMEPPVPCHY EDLERLPDAA EPCLPGALFR
     1021 CPVVFRQEIL VQVIGTLELV GEIEASSMFS LCSSLSISFN SSKHFHLYGS NASLAQVVMK
     1081 VDVVYEKQML YLYVLSGIGG LLLLLLIFIV LYKVGFFKRN LKEKMEAGRG VPNGIPAEDS

                                              ^^^^^^ heterodimerization
     1141 EQLASGQEAG DPGCLKPLHE KDSESGGGKD
Transmembrane length 24 (29?)   Cytoplasmic length (53?) 58
24/58 given by Swiss-Prot. 29/53 given by Larson's original sequence (and recently agreed to by Nancy Hogg).
Heterodimerization & GFFKR motif: see Pardi, Peter, O'Toole. GFFKR is conserved in all integrin alpha chains ( Song).
Discrepancy: Position 189 was Trp(W) in the sequence reported by Larson et al., but Arg(R) in that reported by Qu & Leahy. The former cDNA clone was obtained from cell line U-937, a monocytic cell line derived from the lymphoma of a 37 year old male, while the latter came from THP-1, a human monocytic cell line derived from a 1 year old male patient with acute monocytic leukemia.

Crystallographically Determined Secondary Structure of the I domain

1LFA: Qu & Leahy's 1LFA Alpha helix   Beta strand as given in 1LFA.PDB. RasMol's determination (said to be by Kabsch & Sander's DSSP algorithm) agrees quite well (tho not quite perfectly) with that in the PDB file. However, the helix and strand ranges given in Qu & Leahy's paper, said to be from PROCHECK's implementation of the Kabsch & Sander algorithm, agree with neither the PDB file nor the NCBI record.
NCBI: Qu & Leahy's 1LFA Alpha helix   Beta strand as given by NCBI Entrez, which quotes the PDB as the source. 

1LFA  121                                C IKGNVDLVFL FDGSMSLQPD EFQKILDFMK
NCBI  121                                C IKGNVDLVFL FDGSMSLQPD EFQKILDFMK

1LFA  181 DVMKKLSNTS YQFAAVQFST SYKTEFDFSD YVKRKDPDAL LKHVKHMLLL TNTFGAINYV
NCBI  181 DVMKKLSNTS YQFAAVQFST SYKTEFDFSD YVKRKDPDAL LKHVKHMLLL TNTFGAINYV

1LFA  241 ATEVFREELG ARPDATKVLI IITDGEATDS GNIDAAKDII RYIIGIGKHF QTKESQETLH
NCBI  241 ATEVFREELG ARPDATKVLI IITDGEATDS GNIDAAKDII RYIIGIGKHF QTKESQETLH

1LFA  301 KFASKPASEF VKILDTFEKL KDLFTELQKK IYVIEG
NCBI  301 KFASKPASEF VKILDTFEKL KDLFTELQKK IYVIEG

Feedback to Eric Martz.