Fig. 1. Anatomical structure of the human epididymis (adapted from Turner (1995)). In this study, the epididymis was subdivided into caput, corpus and cauda as shown.

Fig. 2. Profile of transcripts throughout the epididymis (A) and region-specific transcripts of caput, corpus and cauda (B). All qualifiers were designated as “present” by GCOS software analysis and their relative intensity was not less than 50. “Regions in common” means these qualifiers were all present in caput, corpus and cauda.

Fig. 3. Functional classification of qualifiers from the array analysis results of the three regions in human epididymis. The qualified transcripts must be “present” in one segment of the epididymis and the relative intensity was not less than 50 (A) or 2500 (B).

Fig. 4. Number of genes and ESTs showing region-specific pattern of expression (EP, epididymis).

Fig. 5. Functional classification of region-specific genes in human epididymis. The genes were grouped based on their known or predicted cellular location and function.

Fig. 6. Number of transcripts showing changes in expression between two epididymal regions. The vertical scale represents the total number of transcripts that show at least 2-, 4-, 50- or 100-fold changes in either direction. The numbers above and below each vertical bar represent how many transcripts that show increased and decreased expression, respectively, when compared with the reference region. For instance, in caput region, 1067 transcripts were expressed at relative levels two-fold greater than those in corpus, and 1573 transcripts with expression levels two-fold lower than those in corpus.

Fig. 7. Expression patterns of members of the beta defensin family in human epididymis. Different patterns are represented by thin solid, thick solid and dotted line. The expression of other β-defensins (DEFB4, 103, 108, 122, and 124) is not shown since they could not be detected.

Fig. 8. Expression pattern of serpin (serine-rich protease inhibitor) family genes along the human epididymis.

Fig. 9. Expression of aquaporin family genes in the three regions of the human epididymis.

Fig. 10. Expression pattern of caspase (cysteine aspartic acid specific protease) family genes along the human epididymis. Three different patterns emerge and they are indicated by the thin solid, thick solid and dotted line.

Classification of qualifiers throughout the epididymis or specific to one region

Caput-specific genes with relative intensity not less than 100 and never reported before to be expressed in the epididymis

Corpus-specific genes never reported before to be expressed in the epididymis

Cauda-restricted genes never reported previously to be expressed in the epididymis

Evaluation of microarray results by comparing with previously identified expression pattern of several human epididymis-specific genes

Validation of microarray results by comparing with Northern blot analysis results of several epididymis-specific genes in monkey

NA = not available.