Download presentation
Presentation is loading. Please wait.
Published byJean-Christophe Dumont Modified over 5 years ago
1
Extracellular Proteins Needed for C. elegans Mechanosensation
Hongping Du, Guoqiang Gu, Chris M William, Martin Chalfie Neuron Volume 16, Issue 1, Pages (January 1996) DOI: /S (00)
2
Figure 1 Mapping of mec-5 and Fusion Constructs
(A) The genetic and physical maps near mec-5. The top line represents the genetic map near mec-5. Cosmid E03G2 rescues mec-5 mutants, but cosmid C09G1 does not. The positions and rescuing abilities of subclones of E03G2 are given below the partial restriction map of the cosmid. B, BamHI; Bs, BstEII; K, KpnI; R, EcoRI; S, SacI; Sa, Sau3A; X, XbaI; +, >95% of the transformants were rescued; −, none of the transformants were rescued. (B) mec-5 fusion constructs. Fusion TU#235 also contains sequences encoding a synthetic transmembrane domain (denoted by S) before the lacZ sequences. Neuron , DOI: ( /S (00) )
3
Figure 1 Mapping of mec-5 and Fusion Constructs
(A) The genetic and physical maps near mec-5. The top line represents the genetic map near mec-5. Cosmid E03G2 rescues mec-5 mutants, but cosmid C09G1 does not. The positions and rescuing abilities of subclones of E03G2 are given below the partial restriction map of the cosmid. B, BamHI; Bs, BstEII; K, KpnI; R, EcoRI; S, SacI; Sa, Sau3A; X, XbaI; +, >95% of the transformants were rescued; −, none of the transformants were rescued. (B) mec-5 fusion constructs. Fusion TU#235 also contains sequences encoding a synthetic transmembrane domain (denoted by S) before the lacZ sequences. Neuron , DOI: ( /S (00) )
4
Figure 2 Northern Blot Analysis of mec-5 and mec-9
Neuron , DOI: ( /S (00) )
5
Figure 3 Deduced Amino Acid Sequence of MEC-5 and Distribution of mec-5 Mutations (A) The MEC-5 sequence. The signal sequence is shaded; Gly-X-Y regions are boxed. (B) Positions of mec-5 mutations. The boxed regions are the Gly-X-Y repeats. The diamond indicates the position of the silent mutation u753; open circles denote temperature-sensitive alleles; closed circles denote alleles that are not temperature sensitive. Neuron , DOI: ( /S (00) )
6
Figure 4 β-Galactosidase Expression from a mec-5–lacZ Fusion (TU#235)
(A) Newly hatched larva. (B) L2 stage larva. Neuron , DOI: ( /S (00) )
7
Figure 5 mec-9 Transcripts, Reporter Fusions, and Mutations
(A) The positions of the long and short transcripts are given in relation to the 10 kb PstI fragment that rescues the mutant phenotype. The primers (PR-F#) used to determine the 5′ ends of the transcripts (see Experimental Procedures) are positioned on the transcripts. The arrowhead indicates that the short transcript is SL1 trans-spliced. K, KpnI; P, PstI; S, StyI; V, EcoRV; X, XmnI. (B) Mutations in mec-9 are positioned along the protein sequences. Neuron , DOI: ( /S (00) )
8
Figure 6 Predicted Sequences for MEC-9L and MEC-9S
The MEC-9L sequence is given in its entirety. Only the beginning of MEC-9S is given; it continues with the sequence beginning at the triangle. Hydrophobic regions are italicized, Kunitz domains are in shaded boxes, EGF repeats are in unshaded boxes, and asterisks are placed under putative N-glycosylation sites. Neuron , DOI: ( /S (00) )
9
Figure 7 Alignment of the Kunitz and EGF Repeats from MEC-9L
(A) The MEC-9L Kunitz repeats are compared to the first Kunitz domain of inter-α-trypsin inhibitor (IATR) of horse (Hochstrasser et al. 1985) as an example. The disulfide bonds (Laskowski and Kato 1980) are depicted by lines. The reactive site residue (P1) is marked by an arrowhead. The residues marked by asterisks are conserved in this family of repeats (Goldenberg et al. 1989). (B) The mec-9 EGF-like repeats are compared to the mouse EGF precursor (Gray et al. 1983; Scott et al. 1983). Disulfide bonds (Davis 1990) are depicted by lines. The conserved residues for the Ca2+-binding EGF-like repeats (Davis 1990) are shown beneath the mouse EGF sequence. Neuron , DOI: ( /S (00) )
10
Figure 8 β-Galactosidase Expression from mec-9–lacZ Fusions
All animals are L4 larvae. (a) Long transcript expression in the touch receptor neurons from TU#165. (b) Short transcript expression from TU#160 in some ventral cord motor neurons and cells in the head. (c) Expression from both transcripts using TU#171. Both sets of cells stain. Neuron , DOI: ( /S (00) )
Similar presentations
© 2024 SlidePlayer.com. Inc.
All rights reserved.