Analysis of tarantula skeletal muscle protein sequences and identification of transcriptional isoforms
UMass Chan Affiliations
Department of Cell BiologyDocument Type
Journal ArticlePublication Date
2009-03-21Keywords
Amino Acid SequenceAnimals
DNA
Expressed Sequence Tags
Gene Expression Profiling
Gene Library
Molecular Sequence Data
Muscle Proteins
Muscle, Skeletal
Protein IsoformsSequence AlignmentSequence Analysis, DNASpidersCell Biology
Metadata
Show full item recordAbstract
BACKGROUND: Tarantula has been used as a model system for studying skeletal muscle structure and function, yet data on the genes expressed in tarantula muscle are lacking. RESULTS: We constructed a cDNA library from Aphonopelma sp. (Tarantula) skeletal muscle and got 2507 high-quality 5'ESTs (expressed sequence tags) from randomly picked clones. EST analysis showed 305 unigenes, among which 81 had more than 2 ESTs. Twenty abundant unigenes had matches to skeletal muscle-related genes including actin, myosin, tropomyosin, troponin-I, T and C, paramyosin, muscle LIM protein, muscle protein 20, a-actinin and tandem Ig/Fn motifs (found in giant sarcomere-related proteins). Matches to myosin light chain kinase and calponin were also identified. These results support the existence of both actin-linked and myosin-linked regulation in tarantula skeletal muscle. We have predicted full-length as well as partial cDNA sequences both experimentally and computationally for myosin heavy and light chains, actin, tropomyosin, and troponin-I, T and C, and have deduced the putative peptides. A preliminary analysis of the structural and functional properties was also carried out. Sequence similarities suggested multiple isoforms of most myofibrillar proteins, supporting the generality of multiple isoforms known from previous muscle sequence studies. This may be related to a mix of muscle fiber types. CONCLUSION: The present study serves as a basis for defining the transcriptome of tarantula skeletal muscle, for future in vitro expression of tarantula proteins, and for interpreting structural and functional observations in this model species.Source
BMC Genomics. 2009 Mar 19;10:117.Permanent Link to this Item
http://hdl.handle.net/20.500.14038/27679PubMed ID
19298669Related Resources
Link to Article in PubMedRights
© 2009 Zhu et al; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Link to article on publisher's siteCollections
Related items
Showing items related by title, author, creator and subject.
-
Chlamydomonas IFT88 and its mouse homologue, polycystic kidney disease gene tg737, are required for assembly of cilia and flagellaIntraflagellar transport (IFT) is a rapid movement of multi-subunit protein particles along flagellar microtubules and is required for assembly and maintenance of eukaryotic flagella. We cloned and sequenced a Chlamydomonas cDNA encoding the IFT88 subunit of the IFT particle and identified a Chlamydomonas insertional mutant that is missing this gene. The phenotype of this mutant is normal except for the complete absence of flagella. IFT88 is homologous to mouse and human genes called Tg737. Mice with defects in Tg737 die shortly after birth from polycystic kidney disease. We show that the primary cilia in the kidney of Tg737 mutant mice are shorter than normal. This indicates that IFT is important for primary cilia assembly in mammals. It is likely that primary cilia have an important function in the kidney and that defects in their assembly can lead to polycystic kidney disease.
-
ATF1 and CREB trans-activate a cell cycle regulated histone H4 gene at a distal nuclear matrix associated promoter elementProteins of the ATF/CREB class of transcription factors stimulate gene expression of several cell growth-related genes through protein kinase A-related cAMP response elements. The promoter activity of cell cycle regulated histone H4 genes is regulated by at least four principal cis-acting elements which mediate G1/S phase control and/or enhancement of transcription during the cell cycle. Using protein-DNA interaction assays we show that the H4 promoter contains two ATF/CREB recognition motifs which interact with CREB, ATF1, and ATF2 but not with ATF4/CREB2. One ATF/CRE motif is located in the distal promoter at the nuclear matrix-associated Site IV, and the second motif is present in the proximal promoter at Site I. Both ATF/CRE motifs overlap binding sequences for the multifunctional YY1 transcription factor, which has previously been shown to be nuclear matrix associated. Subnuclear fractionation reveals that there are two ATF1 isoforms which appear to differ with respect to DNA binding activity and partition selectively between nuclear matrix and nonmatrix compartments, consistent with the role of the nuclear matrix in regulating gene expression. Site-directed mutational studies demonstrate that Site I and Site IV together support ATF1- and CREB-induced trans-activation of the H4 promoter. Thus, our data establish that ATF/CREB factors functionally modulate histone H4 gene transcription at distal and proximal promoter elements.
-
The unique catalytic subunit of sperm cAMP-dependent protein kinase is the product of an alternative Calpha mRNA expressed specifically in spermatogenic cellscAMP-dependent protein kinase has a central role in the control of mammalian sperm capacitation and motility. Previous protein biochemical studies indicated that the only cAMP-dependent protein kinase catalytic subunit (C) in ovine sperm is an unusual isoform, termed C(s), whose amino terminus differs from those of published C isoforms of other species. Isolation and sequencing of cDNA clones encoding ovine C(s) and Calpha1 (the predominant somatic isoform) now reveal that C(s) is the product of an alternative transcript of the Calpha gene. C(s) cDNA clones from murine and human testes also were isolated and sequenced, indicating that C(s) is of ancient origin and widespread in mammals. In the mouse, C(s) transcripts were detected only in testis and not in any other tissue examined, including ciliated tissues and ovaries. Finally, immunohistochemistry of the testis shows that C(s) first appears in pachytene spermatocytes. This is the first demonstration of a cell type-specific expression for any C isoform. The conservation of C(s) throughout mammalian evolution suggests that the unique structure of C(s) is important in the subunit's localization or function within the sperm.
