Transmembrane sequence

Munter LM, Voigt P, Harmeier A et al (2007). GxxxG motifs within the amyloid precursor protein transmembrane sequence are critical for the etiology of AB42. EMBO 126 1702-1712... 

Figure 47-10. Schematic diagram of the structure of human L-selectin. The extracellular portion contains an amino terminal domain homologous to C-type lectins and an adjacent epidermal growth factor-like domain. These are followed by a variable number of complement regulatory-like modules (numbered circles) and a transmembrane sequence (blackdiamond). A short cytoplasmic sequence (open rectangle) is at the carboxyl terminal. The structures of P- and E-selectin are similar to that shown except that they contain more complement-regulatory modules.The numbers of amino acids in L-, P-, and E- selectins, as deduced from the cDNA sequences, are 385,789, and 589, respectively. (Reproduced, with permission, from Bevilacqua MP, Nelson RM Selectins. J Clin Invest 1993 91 370.)...

Hydropathy analysis predicted that there are four major transmembrane domains (M1-M4) prior to the phosphorylation site at Asp . The existence of these four transmembrane segments in the N-terminal half of the catalytic subunit is generally accepted for all P-type ATPases. The four transmembrane sequences are followed by a large cytosolic loop that contains the phosphorylation site Asp, the pyridoxal... 

The assignment of the six additional transmembrane helices (M5-M10) is less conclusive. Since both the N-terminal and the C-terminal segments of the Ca " -ATPase molecule are exposed on the cytoplasmic surface of the membrane [112,135-138], the number of transmembrane sequences must be even, probably eight or ten odd numbered transmembrane domains (seven or nine) appear to be excluded [138,139]. 

Fig. 20.2. Percentage of amino acids with H-bond donor side chains in the 12 putative transmembrane sequences of P-glycoprotein (P-gp). The transmembrane sequences were determined by means of a hydropathy plot according to Kyte and Doolitttle [100] and chosen to be 22 amino acids long. The first amino acid of each transmembrane sequence...

T-cell antigen receptors belong to a separate family, which is composed of eight noncovalently bound trans-membrane subunits. The central ligand-binding element is a disulfide linked a,/1-heterodimer linked to the membrane by a short transmembrane sequence. The dimeric, variable subunits are the cellular equi-... 

Postsynaptic membrane Ionic channel Glycoprotein Transmembrane. SEQUENCE 440 AA 50640 MW 375043BA CRC32 ... 

Type XXIII collagen contains about 540 residues. The NCI domain contains a transmembrane sequence and is followed by COLl, NC2, COL2, NC3, COL3, and NC4 at the C-terminus. Furin proteinases may cleave the NCI domain, and the cleaved secreted portion of type XXIII collagen may also form multimers and display low-affinity binding to heparin in vitro ... 

Tyler, B.M., Cowman, A.F., Gerondakis, S.D., Adams, J.M., Bernard, O. (1982). mRNA for surface immunoglobulin y chains encodes a highly conserved transmembrane sequence and a 28-residue intracellular domain. Proc. Natl. Acad. Sci. USA 79,2008-2012. 

Barak LS, Menard L, Ferguson SS, Colapietro AM, Caron MG. The conserved seven-transmembrane sequence NP(X)2,3Y of the G protein-coupled receptor superfamily regulates multiple properties of the beta 2-adreneigic receptor. Biochemistry 1995 34 15,407-15,414. 

Much more is known about the interaction of cells with laminin. A high-affinity (Ad = 1 x 10 9 to 4 x 10-9) receptor for laminin has been found on many cells including myoblasts, tumor cells, and macrophages (Lesot et al., 1983 Rao et al., 1983 Malinoff and Wicha, 1983). The laminin receptor (Mr 67K) is solubilized by detergent and has all the characteristics of an integral membrane protein. A partial amino acid sequence of the receptor has been deduced from the nucleotide sequence of cDNA clones. These show a possible transmembrane sequence and suggest that this receptor has substantial cytoplasmic and extracellular domains (Wewer et al., 1986). 

Fig. 3. The transmembrane sequences of the rat c-neu and one-neu proteins showing the position of the activating mutation.

After the introduction of gene cloning methodologies, three new receptor subtypes, D3, D4 and D5, were characterized over the years. Characterization of complementary DNA for all five receptor subtypes showed that D3 and D5 receptors share high homology in their transmembrane sequences similarly, the transmembrane sequences of D2, D3 and D4 receptors are conserved in the three receptor species (Missale et al., 1998). 

Figure 6. Alignment of archaeal PI synthase homologues with the M. bovis PI synthase (My.b.) Ms.a., Methanosarcina acetivorans Mb.t., Methanobacterium thermoautotrophicum Py.f., Pyro-coccus furiosus. The transmembrane sequence of the M. bovis enzyme is in italics while the CDP-alcohol transferase domain is underlined.

Akiyama Y, Kanehara K, Ito K. RseP (YaeL), an Escherichia 33. coli RIP protease, cleaves transmembrane sequences. EMBO J. 2004 23 4434-4442. 

Figure 18.1 The putative transmembrane domains of P-gp derived from hydropathy plots. Hydropathy analyses search for all clusters of about 20-22 amino acids in a protein, which are hydrophobic enough to form a transmembrane sequence. Upper panel P-gp in a 2D model derived from hydropathy plots comprises two halves each consisting of six putative a-helices...

Signal sequences represent a larger class of polypeptide sequences which share the characteristic of performing their functions by virtue of gross structural features and physical behavior in distinct environments. Other examples most likely include transmembrane sequences, viral fusion sequences, membrane entry sequences in toxins, and signal peptides of mitochondria and chloroplasts. These sequences are unlike seg-... 

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