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Previous study has shown that the internal motor kinesin AtKinesin-13A is associated with Golgi stacks in various Arabidopsis cells. With degenerate primers, a segment of 2067 bp was cloned from tobacco by RT-PCR. The polypeptide coded by the segment has 77.33% similarities with the corresponding part of AtKinesin-13A from Arabidopsis; and antibody of AtKinesin-13A recognized specifically the expressed products of the segment in bacteria. Using the anti-AtKinesin-13A antibodies, a 120 kD polypeptide was detected from protein extracts of various organs from Nicotiana tabacum, indicating that a homologue of AtKinesin-13A protein, NtKinesin-13A, is expressed in Nicotiana tabacum. Immunofluorescence staining showed that the tobacco NtKinesin-13A protein appeared in particles in pollen tubes by confocal microscopy. Immunofluorescence double labeling showed that the NtKinesin-13A protein particles partially co-distributed with 58K protein, indicating that NtKinesin-13A is located on Golgi apparatus. Immuno-gold labeling and electron microscopy observation revealed that the NtKinesin-13A was associated with Golgi-associated vesicles membranes in tobacco pollen tubes. These results suggest that the NtKinesin-13A may probably play an important role in controlling Golgi stacks, and/or in transporting Golgi- derived vesicles in pollen tubes.