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1.
Summary
Bumetanide-sensitive Na-K-Cl cotransporters and thiazide-sensitive Na-Cl cotransporters comprise a family of integral membrane
transport proteins, the Na-K-Cl cotransporter (NKCC) family. Each of the members of this family is over 1,000 amino acids
in length. We have multiply aligned the ten currently sequenced members of this family from human, rabbit, rodent, shark,
flounder, moth, worm and yeast sources. Phylogenetic analyses suggest the presence of at least six isoforms of these full
length proteins in eukaryotes. Average hydropathy and average similarity plots have been derived revealing that each of these
proteins possesses a central, well conserved, hydrophobic domain of almost invariant length, possibly consisting of twelve
transmembrane α-helical spanners, an N-terminal, poorly conserved, hydrophilic domain of variable length, and a C-terminal,
moderately conserved, hydrophilic domain of moderately constant length. A functionally uncharacterized homologue of this family
occurs in the cyanobacterium Synechococcus sp. Limited sequence similarity of these proteins with members of a family of basic amino acid transporters suggests that the
NKCC family may be distantly related to the previously characterized, ubiquitous, amino acid-polyamine-choline (APC) family
of facilitators. These observations suggest that the NKCC family is an old family that has its roots in the prokaryotic kingdom.
Received: 27 July 1995/Revised: 8 November 1995 相似文献
2.
The ubiquitous major intrinsic protein (MIP) family includes several transmembrane channel proteins known to exhibit specificity
for water and/or neutral solutes. We have identified 84 fully or partially sequenced members of this family, have multiply
aligned over 50 representative, divergent, fully sequenced members, have used the resultant multiple alignment to derive current
MIP family-specific signature sequences, and have constructed a phylogenetic tree. The tree reveals novel features relevant
to the evolutionary history of this protein family. These features plus an evaluation of functional studies lead to the postulates:
(i) that all current MIP family proteins derived from two divergent bacterial paralogues, one a glycerol facilitator, the
other an aquaporin, and (ii) that most or all current members of the family have retained these or closely related physiological
functions.
Received: 19 April 1996/Revised: 3 June 1996 相似文献
3.
Christine P. Piotte Airlie K. Hunter Craig J. Marshall Murray R. Grigor 《Journal of molecular evolution》1998,46(3):361-369
Three proteins have been identified in the milk of the common brush tail possum, Trichosurus vulpecula that from sequence analysis are members of the lipocalin family. They include β-lactoglobulin, which appears to have two
forms; a homologue to the late-lactation protein found in tammar, Macropus eugenii; milk; and a novel protein termed trichosurin. Whereas β-lactoglobulin and trichosurin are both expressed throughout lactation, the late-lactation protein is not detected
in samples taken before days 100–110 of lactation. The cDNAs encoding each of these proteins have been isolated from cDNA
libraries prepared using possum mammary mRNA and sequenced. Phylogenetic analysis showed that the T. vulpeculaβ-lactoglobulin, along with two other macropod β-lactoglobulins, forms a subclass of β-lactoglobulins distinct from those
for eutherian mammals; both marsupial late-lactation proteins appear to have similarities to a family of odorant-binding proteins,
whereas trichosurin has similarities to the major urinary proteins of rodents.
Received: 28 October 1996 / Accepted: 19 May 1997 相似文献
4.
Alessandra Bonci Alessandra Chiesurin Patrizia Muscas Gian Maria Rossolini 《Journal of molecular evolution》1997,44(3):299-309
The structure of a Salmonella enterica serovar typhi gene located within the fim gene cluster and encoding a putative periplasmic chaperone-like protein involved in the assembly of type 1 pili was determined.
This gene, named fimC, has the ability to encode a 26-kDa polypeptide which is similar, at the sequence level, to the PapD periplasmic chaperonin
mediating the assembly of P pili of Escherichia coli, as well as to other periplasmic chaperone-like proteins involved in the biogenesis of pili or capsule-like structures of
various Gram-negative bacteria. A comprehensive search through the literature and sequence databases identified 31 (putative)
bacterial proteins that can be included in this protein family on the basis of sequence similarity. Results of a multiple
sequence comparison analysis showed that several residues, including most of those known to be critical in maintaining the
three-dimensional structure of PapD, are either conserved or conservatively substituted in all these proteins, suggesting
an overall similar folding for all of them. It was also evident that members of this family are clustered into different subfamilies
according to structural and phyletic data.
Received: 15 February 1996 / Accepted: 3 October 1996 相似文献
5.
We have isolated a 29,000-Da carbonic anhydrase (CA) protein from the zebrafish, Danio rerio, sequenced two peptide fragments, and tentatively identified it as a high-activity CA by inhibition kinetics. We have also
characterized a 1,537-bp message whose deduced sequence of 260 amino acids matches that of the isolated protein. This CA is
clearly an α-CA based on the similarity of its sequence to that of other members of the α-CA gene family. A phylogenetic analysis
suggested CAH-Z diverged after the branching of the CA-V and CA-VII genes and prior to the duplications that generated the
CA-I, CA-II, and CA-III genes of amniotes. This marks the first characterization of the mRNA and its protein product from
the CA gene of a teleost.
Received: 31 March 1996 / Accepted: 8 September 1996 相似文献
6.
A family of four satellite DNAs has been characterized in the genome of the bivalve mollusc, Donax trunculus. All share HindIII sites, a similar monomer length of about 160 base pairs (bp), and the related oligonucleotide motifs GGTCA and GGGTTA,
repeated six to 15 times within the repetitive units. The motif GGTCA is common to all members of the satellite family. It
is present in three of them in both orientations, interspersed within nonrepetitive DNA sequences. The hexanucleotide GGGTTA
appears to be the main building element of one of the satellites forming a prominent subrepeat structure in conjunction with
the 5-bp motif. The former has been also found in perfect tandem repeats in a junction region adjacent to the proper satellite
sequence. Southern analysis has revealed that (GGGTTA)n and/or related sequences are abundant and widely distributed in the D. trunculus genome. The distribution observed is consistent with the concurrence of the scattering of short sequence motifs throughout
the genome and the spread of longer DNA segments, with concomitant formation of satellite monomer repeats. Both kinds of dispersion
may have contributed to the observed complex arrangement of the HindIII satellite DNA family in Donax.
Received: 28 May 1996 / Accepted: 30 July 1996 相似文献
7.
A number of proteins have been identified that contain prominent sequence signatures that are uniquely shared by the members
of the Deinococcus-Thermus genera and the cyanobacterial species but which are not found in any of the other eubacterial or archaebacterial homologs.
The proteins containing such sequence signatures include (1) the DnaJ/Hsp40 family of proteins, (2) DNA polymerase I, (3)
the protein synthesis elongation factor EF-Tu, and (4) the elongation factor EF-Ts. A strong affinity of the Deinococcus-Thermus species to cyanobacteria is also seen in the phylogenetic trees based on Hsp70 and DnaJ sequences. These results provide
strong evidence of a close and specific evolutionary relationship between species belonging to these two eubacterial divisions.
Received: 10 September 1997 / Accepted: 15 December 1997 相似文献
8.
Sequence Analyses and Phylogenetic Characterization of the ZIP Family of Metal Ion Transport Proteins 总被引:1,自引:0,他引:1
Several novel but similar heavy metal ion transporters, Zrt1, Zrt2, Zip1-4 and Irt1, have recently been characterized. Zrt1,
Zrt2 and Zip1-4 are probably zinc transporters in Saccharomyces cerevisiae and Arabidopsis thaliana whereas Irt1 appears to play a role in iron uptake in A. thaliana. The family of proteins including these functionally characterized transporters has been designated the Zrt- and Irt-related
protein (ZIP) family. In this report, ZIP family proteins in the current databases were identified and multiply aligned, and
a phylogenetic tree for the family was constructed. A family specific signature sequence was derived, and the available sequences
were analyzed for residues of potential functional significance. A fully conserved intramembranous histidyl residue, present
within a putative amphipathic, α-helical, transmembrane spanning segment, was identified which may serve as a part of an intrachannel
heavy metal ion binding site. The occurrence of a proposed extramembranal metal binding motif (H X H X H) was examined in
order to evaluate its potential functional significance for various members of the family. The computational analyses reported
in this topical review should serve as a guide to future researchers interested in the structure-function relationships of
ZIP family proteins.
Received: 31 March 1997/Revised: 14 May 1998 相似文献
9.
Evolutionary Relationship of the Ligand-Gated Ion Channels and the Avermectin-Sensitive,Glutamate-Gated Chloride Channels 总被引:4,自引:0,他引:4
Demetrios K. Vassilatis Keith O. Elliston Philip S. Paress Michel Hamelin Joseph P. Arena James M. Schaeffer Lex H.T. Van der Ploeg Doris F. Cully 《Journal of molecular evolution》1997,44(5):501-508
Two cDNAs, GluClα and GluClβ, encoding glutamate-gated chloride channel subunits that represent targets of the avermectin
class of antiparasitic compounds, have recently been cloned from Caenorhabditis elegans (Cully et al., Nature, 371, 707–711, 1994). Expression studies in Xenopus oocytes showed that GluClα and GluClβ have pharmacological profiles distinct from the glutamate-gated cation channels as
well as the γ-aminobutyric acid (GABA)- and glycine-gated chloride channels. Establishing the evolutionary relationship of
related proteins can clarify properties and lead to predictions about their structure and function. We have cloned and determined
the nucleotide sequence of the GluClα and GluClβ genes. In an attempt to understand the evolutionary relationship of these
channels with the members of the ligand-gated ion channel superfamily, we have performed gene structure comparisons and phylogenetic
analyses of their nucleotide and predicted amino acid sequences. Gene structure comparisons reveal the presence of several
intron positions that are not found in the ligand-gated ion channel superfamily, outlining their distinct evolutionary position.
Phylogenetic analyses indicate that GluClα and GluClβ form a monophyletic subbranch in the ligand-gated ion channel superfamily
and are related to vertebrate glycine channels/receptors. Glutamate-gated chloride channels, with electrophysiological properties
similar to GluClα and GluClβ, have been described in insects and crustaceans, suggesting that the glutamate-gated chloride
channel family may be conserved in other invertebrate species. The gene structure and phylogenetic analyses in combination
with the distinct pharmacological properties demonstrate that GluClα and GluClβ belong to a discrete ligand-gated ion channel
family that may represent genes orthologous to the vertebrate glycine channels.
Received: 30 September 1996 / Accepted: 15 November 1996 相似文献
10.
Characterization of a Small Family (CAIII) of Microsatellite-Containing Sequences with X-Y Homology 总被引:4,自引:0,他引:4
Patrizia Malaspina Bianca Maria Ciminelli Luigi Viggiano Carla Jodice Fulvio Cruciani Piero Santolamazza Daniele Sellitto Rosaria Scozzari Luciano Terrenato Mariano Rocchi Andrea Novelletto 《Journal of molecular evolution》1997,44(6):652-659
Four X-linked loci showing homology with a previously described Y-linked polymorphic locus (DYS413) were identified and characterized.
By fluorescent in situ hybridization (FISH), somatic cell hybrids, and YAC screening, the X-linked members of this small family
of sequences (CAIII) all map in Xp22, while the Y members map in Yq11. These loci contribute to the overall similarity of
the two genomic regions. All of the CAIII loci contain an internal microsatellite of the (CA)n type. The microsatellites display extensive length polymorphism in two of the X-linked members as well as in the Y members.
In addition, common sequence variants are found in the portions flanking the microsatellites in two of the X-linked members.
Our results indicate that, during the evolution of this family, length variation on the Y chromosome was accumulated at a
rate not slower than that on the X chromosome. Finally, these sequences represent a model system with which to analyze human
populations for similar X- and Y-linked polymorphisms.
Received: 29 July 1996 / Accepted: 15 January 1997 相似文献