A rare TaqI polymorphism in a human complement C4 gene is caused by an additional restriction site in the first intron

SUMMARYAvian Plasmodium and Haemoproteus parasites are easily detected by DNA analyses of infected samples but only correctly assigned to each genus by sequencing and use of a phylogenetic approach. Here, we present a restriction site to differentiate between both parasite genera avoiding the use of those analyses. Alignments of 820 sequences currently listed in GenBank encoding a particular cytochrome B region of avian Plasmodium and Haemoproteus show a shared restriction site for both genera using the endonuclease Hpy CH4III. An additional restriction site is present in Plasmodium sequences that would initially allow differentiation of both genera by differential migration of digested products on gels. Overall 9 out of 326 sequences containing both potential restriction sites do not fit to the general rule. We used this differentiation of parasite genera based on Hpy CH4III restriction sites to evaluate the efficacy of 2 sets of general primers in detecting mixed infections. To do so, we used samples from hosts infected by parasites of both genera. The use of general primers was only able to detect 25% or less of the mixed infections. Therefore, parasite DNA amplification using general primers to determine the species composition of haemosporidian infections in individual hosts is not recommended. Specific primers for each species and study area should be designed until a new method can efficiently discriminate both parasites.

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D1/D2 Domain of Large-Subunit Ribosomal DNA for Differentiation of Orpinomyces spp.

Applied and Environmental Microbiology ◽

10.1128/aem.05441-11 ◽

2011 ◽

Vol 77 (18) ◽

pp. 6722-6725 ◽

Cited By ~ 44

Author(s):

Sumit S. Dagar ◽

Sanjay Kumar ◽

Priti Mudgil ◽

Rameshwar Singh ◽

Anil K. Puniya

Keyword(s):

Ribosomal Dna ◽

Restriction Site ◽

Fragment Length Polymorphism ◽

Large Subunit ◽

Species Level ◽

Additional Restriction ◽

Lsu Rdna ◽

Content Type ◽

D2 Domain ◽

Additional Restriction Site

ABSTRACTThis study presents the suitability of D1/D2 domain of large-subunit (LSU) ribosomal DNA (rDNA) for differentiation ofOrpinomyces joyoniiandOrpinomyces intercalarisbased on PCR-restriction fragment length polymorphism (RFLP). A variation of G/T inO. intercalariscreated an additional restriction site for AluI, which was used as an RFLP marker. The results demonstrate adequate heterogeneity in the LSU rDNA for species-level differentiation.

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Effect of methylamine on the structure and function of the fourth component of human complement, C4.

Journal of Biological Chemistry ◽

10.1016/s0021-9258(19)70418-9 ◽

1980 ◽

Vol 255 (21) ◽

pp. 10025-10028

Author(s):

J.P. Gorski ◽

J.B. Howard

Keyword(s):

Structure And Function ◽

Human Complement ◽

Complement C4 ◽

Fourth Component ◽

And Function

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The primary structure of the fourth component of human complement (C4)-C-terminal peptides

Bioscience Reports ◽

10.1007/bf01119904 ◽

1985 ◽

Vol 5 (10-11) ◽

pp. 913-921 ◽

Cited By ~ 6

Author(s):

S. K. Alex Law ◽

Jean Gagnon

Keyword(s):

Primary Structure ◽

Protein Sequence ◽

Human Complement ◽

Cdna Sequencing ◽

Complement C4 ◽

Fourth Component ◽

Polypeptide Chains ◽

Complete Primary Structure

C-terminal CNBr peptides of the three polypeptide chains of C4 were obtained and sequenced. These results supplement previously obtained data, notably the protein sequence derived from cDNA sequencing of pro-C4 (Belt KT, Carroll MC & Porter RR (1984) Cell36, 907–914) and the N-terminal sequences of the three polypeptides (Gigli I, von Zabern I & Porter RR (1977) Biochem. J.165, 439–446), to define the complete primary structure of the plasma form of C4. The β (656 residues), α (748 residues), and γ (291 residues) chains are found in positions 1–656, 661–1408, and 1435–1725 in the pro-C4 molecule.

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A Molecular Switch Governs the Interaction between the Human Complement Protease C1s and Its Substrate, Complement C4

Journal of Biological Chemistry ◽

10.1074/jbc.m113.464545 ◽

2013 ◽

Vol 288 (22) ◽

pp. 15821-15829 ◽

Cited By ~ 17

Author(s):

Andrew J. Perry ◽

Lakshmi C. Wijeyewickrema ◽

Pascal G. Wilmann ◽

Menachem J. Gunzburg ◽

Laura D'Andrea ◽

...

Keyword(s):

Molecular Switch ◽

Human Complement ◽

Complement C4

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Structural differences between the two human complement C4 isotypes affect the humoral immune response.

Journal of Experimental Medicine ◽

10.1084/jem.175.2.537 ◽

1992 ◽

Vol 175 (2) ◽

pp. 537-543 ◽

Cited By ~ 29

Author(s):

O Finco ◽

S Li ◽

M Cuccia ◽

F S Rosen ◽

M C Carroll

Keyword(s):

Immune Response ◽

Animal Model ◽

Humoral Immune Response ◽

Guinea Pigs ◽

Structural Difference ◽

Secondary Response ◽

Human Complement ◽

Complement C4 ◽

Humoral Immune ◽

Structural Differences

An animal model has been used to address the question of the biological importance of the known structural difference between the two isotypes of human C4, i.e., C4A and C4B. Guinea pigs deficient in C4 were reconstituted transiently with either human C4A or C4B protein and immunized with the bacteriophage phi X174. Results from this study showed that C4A-reconstituted animals made a secondary response, i.e., switch from IgM to IgG; whereas the C4B-reconstituted animals did not.

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