title: Conserved lamin A protein expression in differentiated cells in the earthworm Eudrilus eugeniae.
abstract: Lamin A is an intermediate filament protein found in most of the differentiated vertebrate cells but absent in stem cells. It shapes the skeletal frame structure beneath the inner nuclear membrane of the cell nucleus. As there are few studies of the expression of lamin A in invertebrates, in the present work, we have analyzed the sequence, immunochemical conservation and expression pattern of lamin A protein in the earthworm Eudrilus eugeniae, a model organism for tissue regeneration. The expression of lamin A has been confirmed in E. eugeniae by immunoblot. Its localization in the nuclear membrane has been observed by immunohistochemistry using two different rabbit anti-sera raised against human lamin A peptides, which are located at the C-terminus of the lamin A protein. These two antibodies detected 70 kDa lamin A protein in mice and a single 65 kDa protein in the earthworm. The Oct-4 positive undifferentiated blastemal tissues of regenerating earthworm do not express lamin A, while the Oct-4 negative differentiated cells express lamin A. This pattern was also confirmed in the earthworm prostate gland. The present study is the first evidence for the immunochemical identification of lamin A and Oct-4 in the earthworm. Along with the partial sequence obtained from the earthworm genome, the present results suggest that lamin A protein and its expression pattern is conserved from the earthworm to humans.
authors: Department of Biotechnology, Manonmaniam Sundaranar University, Tirunelveli-627012, Tamilnadu, India.
authors: Ramamoorthy M
authors: RM
authors: Kalidas
authors: Department of Biotechnology, Manonmaniam Sundaranar University, Tirunelveli-627012, Tamilnadu, India.
authors: Subramanian Elaiya
authors: SE
authors: Raja
authors: Department of Biotechnology, Manonmaniam Sundaranar University, Tirunelveli-627012, Tamilnadu, India.
authors: Sheik Abdul Kader Nagoor Meeran
authors: SA
authors: Mydeen
authors: Department of Biotechnology, Manonmaniam Sundaranar University, Tirunelveli-627012, Tamilnadu, India.
authors: Selvan Christyraj Johnson Retnaraj
authors: SC
authors: Samuel
authors: Department of Biotechnology, Manonmaniam Sundaranar University, Tirunelveli-627012, Tamilnadu, India.
authors: Selvan Christyraj Jackson
authors: SC
authors: Durairaj
authors: Gopi D
authors: GD
authors: Nino
authors: Department of Biotechnology, Kalasalingam University, Krishnankoil-626126, Tamilnadu, India.
authors: Karuppaiah
authors: K
authors: Palanichelvam
authors: Department of Surgery, Cedars-Sinai Medical Center, Los Angeles, CA, 90048, USA.
authors: Arumugaswami
authors: A
authors: Vaithi
authors: Department of Biotechnology, Manonmaniam Sundaranar University, Tirunelveli-627012, Tamilnadu, India.
authors: Sivasubramaniam
authors: S
authors: Sudhakar
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D002454:Cell Differentiation / Q000502:physiology; D017124:Conserved Sequence; D015870:Gene Expression; D020869:Gene Expression Profiling; D006801:Humans; D007150:Immunohistochemistry; D007381:Intermediate Filament Proteins / Q000096:biosynthesis / Q000235:genetics; D034904:Lamin Type A / Q000096:biosynthesis* / Q000235:genetics*; D008969:Molecular Sequence Data; D009685:Nuclear Envelope / Q000378:metabolism; D050814:Octamer Transcription Factor-3 / Q000096:biosynthesis / Q000235:genetics; D009835:Oligochaeta / Q000235:genetics* / Q000378:metabolism; D012038:Regeneration / Q000235:genetics / Q000502:physiology; D016415:Sequence Alignment; D020539:Sequence Analysis, Protein
chemical_list: D007381:Intermediate Filament Proteins; D034904:Lamin Type A; D050814:Octamer Transcription Factor-3
keywords: Oct-4; blastema; earthworm; intermediate filament (IF); lamin A; regeneration; stem cell