As an extension of a series of projects for sequencing human cDNA clones derived from relatively long transcripts, we herein report the entire sequences of 100 newly determined cDNA clones with the potential of coding for large proteins in vitro. The cDNA clones were isolated from size-fractionated human brain cDNA libraries with insert sizes between 4.5 and 8.3 kb. The sequencing of these clones revealed that the average size of the cDNA inserts and of their open reading frames was 5.3 kb and 2.8 kb (930 amino acid residues), respectively. Homology search against public databases indicated that the predicted coding sequences of 86 clones exhibited significant similarities to known genes; 51 of them (59%) were related to those for cell signaling/communication, nucleic acid management, and cell structure/motility. All the clones characterized in this study are accompanied by their expression profiles in 14 human tissues examined by reverse transcription-coupled polymerase chain reaction and the chromosomal mapping data.